feat(offline): hotseat in-game seat lock + host menu

Game.svelte drives a hotseat game:
- the seat-to-move's rack is replaced by an Unlock button when the seat
  is PIN-locked (board stays visible); canMove gates the move controls
  on the unlock; PinPad(verify) -> source.unlockSeat reveals it.
- the hint slot becomes a host button (hints off in hotseat), always
  enabled while the game runs (acts on a locked seat too). Master-PIN ->
  action sheet: skip current / exclude a player / end the game, each with
  a confirm + a fading check; terminate deletes and returns to the lobby.
- per-turn advance re-fetches the next seat's (locked) state; self-resign
  and chat are hidden (hotseat resign is a host action, no comms).
- gamesource: expose unlockSeat / verifyHostPin / hostAction on the local
  proxy. i18n hotseat.* (en + ru).

ui/src/game/Game.svelte

@@ -4,6 +4,7 @@
   import TabBar from '../components/TabBar.svelte';
   import TapConfirm from '../components/TapConfirm.svelte';
   import Modal from '../components/Modal.svelte';
+  import PinPad from '../components/PinPad.svelte';
   import DictWarmup from '../components/DictWarmup.svelte';
   import Board from './Board.svelte';
   import Rack from './Rack.svelte';
@@ -163,6 +164,11 @@
   const playable = $derived(!!view && (view.game.status === 'active' || view.game.status === 'open'));
   const isMyTurn = $derived(!!view && playable && view.game.toMove === view.seat);
   const gameOver = $derived(!!view && view.game.status === 'finished');
+  // Offline hotseat: the seat to move is PIN-locked until its owner enters the seat PIN this turn.
+  // While locked the board stays visible but the rack is withheld and the move controls disabled;
+  // canMove folds the lock into isMyTurn (locked is always false for a network / vs_ai game).
+  const locked = $derived(!!view?.locked);
+  const canMove = $derived(isMyTurn && !locked);
   // The hint badge: this game's allowance remaining plus the LIVE global wallet. Reading the
   // wallet from the profile (not the per-game view snapshot) keeps it correct after a wallet
   // hint was spent in another game (see lib/hints).
@@ -774,8 +780,8 @@
     // rapid placements do not pile up requests on a slow link.
     evalCtrl?.abort();
     evalCtrl = null;
-    // Off-turn the composition is position-only: no score preview or evaluate.
-    if (!isMyTurn) return;
+    // Off-turn (or a locked hotseat seat) the composition is position-only: no score preview.
+    if (!canMove) return;
     const sub = toSubmit(placement);
     if (!sub) return;
     // Instant on-device preview when the game's dictionary is warm; the network otherwise.
@@ -833,12 +839,106 @@
     refreshRecent();
   }
 
+  // --- offline hotseat: seat unlock + host (referee) overrides -------------------
+  let unlockOpen = $state(false); // the current locked seat's owner enters their PIN to reveal the rack
+  // The host menu: 'pin' collects the master PIN, then 'menu' lists the overrides. hostPinEntered is
+  // the verified master PIN, reused to authorise the chosen action (the source re-checks it).
+  let hostMenuStep = $state<'closed' | 'pin' | 'menu'>('closed');
+  let hostPinEntered = $state('');
+  // The pending host action awaiting its confirm ("Skip X's turn?" etc.); null shows the menu list.
+  let hostConfirm = $state<{ action: 'skip' | 'resign' | 'terminate'; seat?: number; name?: string } | null>(null);
+  let hostDone = $state(false); // the transient success ✅ shown after an override
+
+  // hotseatName is the plain display name of a seat by index (hotseat seats are account-less local
+  // players, so no "you"/🤖 resolution is needed — unlike the seat-object seatName used elsewhere).
+  function hotseatName(i: number): string {
+    return view?.game.seats[i]?.displayName ?? '';
+  }
+
+  function startSkip(): void {
+    if (!view) return;
+    hostConfirm = { action: 'skip', seat: view.game.toMove, name: hotseatName(view.game.toMove) };
+  }
+
+  function flashDone(): void {
+    hostDone = true;
+    setTimeout(() => (hostDone = false), 1100);
+  }
+
+  // advanceHotseat re-points the screen at the next seat after a hotseat move: the source has advanced
+  // the turn and re-locked, so a fresh state gives the next seat's rack (empty while it is locked).
+  async function advanceHotseat(): Promise<void> {
+    const st = await source.gameState(id, false);
+    view = st;
+    rackIds = st.rack.map((_, i) => i);
+    placement = newPlacement(st.rack);
+    selected = null;
+    preview = null;
+    setCachedGame(id, st, moves, '');
+  }
+
+  // onUnlock verifies the current seat's PIN through the source (which reveals the rack on success)
+  // and applies the unlocked state; handed to the PIN pad as its verifier.
+  async function onUnlock(pin: string): Promise<boolean> {
+    try {
+      const st = await localSource.unlockSeat(id, pin);
+      view = st;
+      rackIds = st.rack.map((_, i) => i);
+      placement = newPlacement(st.rack);
+      selected = null;
+      return true;
+    } catch {
+      return false;
+    }
+  }
+
+  // verifyHost captures the entered master PIN (reused to authorise the chosen action) and checks it.
+  async function verifyHost(pin: string): Promise<boolean> {
+    hostPinEntered = pin;
+    return localSource.verifyHostPin(id, pin);
+  }
+
+  function hostConfirmText(c: { action: 'skip' | 'resign' | 'terminate'; name?: string }): string {
+    if (c.action === 'skip') return t('hotseat.askSkip', { name: c.name ?? '' });
+    if (c.action === 'resign') return t('hotseat.askExclude', { name: c.name ?? '' });
+    return t('hotseat.askTerminate');
+  }
+
+  async function runHostAction(): Promise<void> {
+    if (!hostConfirm) return;
+    const { action, seat } = hostConfirm;
+    hostConfirm = null;
+    hostMenuStep = 'closed';
+    busy = true;
+    try {
+      const st = await localSource.hostAction(id, hostPinEntered, action, seat);
+      if (st === null) {
+        navigate('/'); // terminated: the game is deleted, so return to the lobby
+        return;
+      }
+      view = st;
+      rackIds = st.rack.map((_, i) => i);
+      placement = newPlacement(st.rack);
+      selected = null;
+      preview = null;
+      moves = (await source.gameHistory(id)).moves; // a skip / resign added a journal move
+      setCachedGame(id, st, moves, '');
+      flashDone();
+    } catch (e) {
+      handleError(e);
+    } finally {
+      busy = false;
+      hostPinEntered = '';
+    }
+  }
+
   async function commit() {
     const sub = toSubmit(placement);
     if (!sub) return;
     busy = true;
     try {
       applyMoveResult(await source.submitPlay(id, sub.tiles, variant));
+      if (view?.game.hotseat) await advanceHotseat();
       haptic('success');
       zoomed = false;
     } catch (e) {
@@ -858,6 +958,7 @@
     busy = true;
     try {
       applyMoveResult(await source.pass(id));
+      if (view?.game.hotseat) await advanceHotseat();
     } catch (e) {
       handleError(e);
     } finally {
@@ -979,6 +1080,7 @@
     busy = true;
     try {
       applyMoveResult(await source.exchange(id, tiles, variant));
+      if (view?.game.hotseat) await advanceHotseat();
     } catch (e) {
       handleError(e);
     } finally {
@@ -1433,13 +1535,17 @@
         {:else}
           <button class="hicon" onclick={onExportClick} aria-label={t('game.exportGcg')}>📤</button>
         {/if}
+      {:else if view.game.hotseat}
+        <!-- Hotseat resign is a host (referee) action, not self-serve; keep the slot empty. -->
+        <span aria-hidden="true"></span>
       {:else}
         <button class="hicon" onclick={onResignClick} disabled={waitingForOpponent} aria-label={t('game.dropGame')}>🏁</button>
       {/if}
       {#if !view.game.multipleWordsPerTurn}<span class="oneword-label">{t('game.oneWordRule')}</span>{/if}
       <!-- A finished AI game has no comms at all (no chat, and the dictionary closes with the
-           game), so the entry is dropped; an active AI game keeps it (it opens the dictionary). -->
-      {#if !(gameOver && view.game.vsAi)}
+           game), so the entry is dropped; an active AI game keeps it (it opens the dictionary).
+           A hotseat game has no chat either (local players, no accounts). -->
+      {#if !(gameOver && view.game.vsAi) && !view.game.hotseat}
         <button class="hicon" onclick={() => navigate(`/game/${id}/chat`)} aria-label={t('game.chat')}>
           {#key chatBlink}<span class="chat-ico" class:blink={chatBlink > 0 && !app.reduceMotion}>💬</span>{/key}
         </button>
@@ -1512,7 +1618,7 @@
       {#if gameOver}
         <strong class="over">{resultText()}</strong>
       {:else if placement.pending.length === 0}
-        <span class="turn-ind">{isMyTurn ? t('game.yourTurn') : turnLabel()}</span>
+        <span class="turn-ind">{view.game.hotseat ? t('hotseat.turnOf', { name: hotseatName(view.game.toMove) }) : isMyTurn ? t('game.yourTurn') : turnLabel()}</span>
       {/if}
       <span class="scores">
         {#if recallOverRack}{:else if preview}{preview.legal ? t('game.previewWords', { words: preview.words.join(', '), n: preview.score }) : t('game.previewIllegal')}{/if}
@@ -1526,28 +1632,40 @@
        a finished game shows the final rack greyed out and the controls disabled. -->
   <div class="rack-row" class:inert={gameOver} data-coach="game-rack">
     <div class="rack-wrap">
-      <Rack
-        slots={rackSlots}
-        {variant}
-        {selected}
-        {landscape}
-        shuffling={shuffling && !app.reduceMotion}
-        draggingId={reorderDragId}
-        dropIndex={reorderTo}
-        ondown={onRackDown}
-      />
+      {#if locked}
+        <!-- A PIN-locked hotseat seat: the rack is withheld until its owner unlocks it. The board
+             above stays visible; only this tray is gated. -->
+        <button class="unlock" onclick={() => (unlockOpen = true)}>🔒 {t('hotseat.unlock')}</button>
+      {:else}
+        <Rack
+          slots={rackSlots}
+          {variant}
+          {selected}
+          {landscape}
+          shuffling={shuffling && !app.reduceMotion}
+          draggingId={reorderDragId}
+          dropIndex={reorderTo}
+          ondown={onRackDown}
+        />
+      {/if}
     </div>
     {#if !gameOver && placement.pending.length > 0 && !recallOverRack}
-      <button class="make" onclick={commit} disabled={busy || !isMyTurn || !netReady || !preview?.legal} aria-label={t('game.makeMove')}>✅</button>
+      <button class="make" onclick={commit} disabled={busy || !canMove || !netReady || !preview?.legal} aria-label={t('game.makeMove')}>✅</button>
     {/if}
   </div>
 {/snippet}
 
 {#snippet controlButtons()}
-  <button class="tab" disabled={busy || !isMyTurn || !netReady} onclick={openExchange}>
+  <button class="tab" disabled={busy || !canMove || !netReady} onclick={openExchange}>
     <span class="sq" data-coach="game-turn">🔄</span><span class="lbl">{t('game.draw')}</span>
   </button>
-  {#if view?.game.vsAi}
+  {#if view?.game.hotseat}
+    <!-- Hotseat: no hints. The freed slot becomes the host (referee) button — always available
+         (even on a locked seat: the host may skip a player who forgot their PIN). -->
+    <button class="tab" disabled={busy || gameOver} onclick={() => (hostMenuStep = 'pin')}>
+      <span class="sq">🔐</span><span class="lbl">{t('hotseat.host')}</span>
+    </button>
+  {:else if view?.game.vsAi}
     <!-- vs_ai hints are unlimited and wallet-free, so no confirm and no count. A 🔒 badge marks the
          idle gate while it is closed; tapping then only explains when it opens (doHint), and the lock
          lifts live at the unlock moment. -->
@@ -1623,6 +1741,55 @@
   </Modal>
 {/if}
 
+<!-- Offline hotseat: unlock the current seat's rack. -->
+{#if unlockOpen && view}
+  <PinPad
+    mode="verify"
+    title={t('hotseat.unlockTitle', { name: hotseatName(view.game.toMove) })}
+    verify={onUnlock}
+    onclose={() => (unlockOpen = false)}
+    onresult={() => (unlockOpen = false)}
+  />
+{/if}
+
+<!-- Offline hotseat: the host (referee) enters the master PIN, then picks an override. -->
+{#if hostMenuStep === 'pin'}
+  <PinPad
+    mode="verify"
+    title={t('hotseat.host')}
+    verify={verifyHost}
+    onclose={() => (hostMenuStep = 'closed')}
+    onresult={() => (hostMenuStep = 'menu')}
+  />
+{/if}
+{#if hostMenuStep === 'menu' && view}
+  <Modal title={t('hotseat.host')} onclose={() => { hostMenuStep = 'closed'; hostConfirm = null; }}>
+    {#if hostConfirm}
+      <p class="host-q">{hostConfirmText(hostConfirm)}</p>
+      <div class="confirm-row">
+        <button class="cancel" onclick={() => (hostConfirm = null)}>{t('common.cancel')}</button>
+        <button class="danger" onclick={runHostAction}>{t('common.ok')}</button>
+      </div>
+    {:else}
+      <div class="host-menu">
+        <button class="host-act" onclick={startSkip}>
+          {t('hotseat.skip')}
+        </button>
+        <div class="host-sub">{t('hotseat.exclude')}</div>
+        {#each view.game.seats as s (s.seat)}
+          <button class="host-seat" onclick={() => (hostConfirm = { action: 'resign', seat: s.seat, name: s.displayName })}>
+            {s.displayName}
+          </button>
+        {/each}
+        <button class="host-act danger" onclick={() => (hostConfirm = { action: 'terminate' })}>{t('hotseat.terminate')}</button>
+      </div>
+    {/if}
+  </Modal>
+{/if}
+{#if hostDone}
+  <div class="host-done" aria-hidden="true">✅</div>
+{/if}
+
 {#if exportOpen}
   <Modal title={t('game.exportGcg')} onclose={() => (exportOpen = false)}>
     <div class="export-opts">
@@ -2122,4 +2289,67 @@
     font-size: 0.62rem;
     line-height: 1;
   }
+  /* --- offline hotseat --- */
+  /* The locked-seat rack overlay: fills the rack tray with an "unlock" button, the board above
+     stays visible. */
+  .unlock {
+    width: 100%;
+    height: 100%;
+    min-height: 44px;
+    border: 1px dashed var(--border);
+    border-radius: var(--radius-sm);
+    background: var(--surface);
+    color: var(--text);
+    font-weight: 600;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    gap: 8px;
+  }
+  .host-menu {
+    display: flex;
+    flex-direction: column;
+    gap: 8px;
+  }
+  .host-act,
+  .host-seat {
+    padding: 12px;
+    border: 1px solid var(--border);
+    border-radius: var(--radius-sm);
+    background: var(--surface);
+    color: var(--text);
+    font-weight: 600;
+    text-align: left;
+  }
+  .host-act.danger {
+    border-color: var(--danger);
+    color: var(--danger);
+  }
+  .host-sub {
+    font-size: 0.8rem;
+    color: var(--text-muted);
+    margin-top: 4px;
+  }
+  .host-q {
+    margin: 0 0 12px;
+    font-weight: 600;
+  }
+  /* The transient success tick after a host override — a centred ✅ that fades out on a timer. */
+  .host-done {
+    position: fixed;
+    inset: 0;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    font-size: 4rem;
+    z-index: 50;
+    pointer-events: none;
+    animation: host-done-fade 1.1s ease forwards;
+  }
+  @keyframes host-done-fade {
+    0% { opacity: 0; transform: scale(0.7); }
+    25% { opacity: 1; transform: scale(1); }
+    75% { opacity: 1; transform: scale(1); }
+    100% { opacity: 0; transform: scale(1); }
+  }
 </style>

ui/src/lib/gamesource.ts

@@ -41,6 +41,11 @@ export const localSource = {
   create: (opts) => load().then((s) => s.create(opts)),
   list: () => load().then((s) => s.list()),
   delete: (id) => load().then((s) => s.delete(id)),
+  // Offline hotseat controls (no network equivalent): reveal a PIN-locked seat, and the host
+  // (referee) overrides gated by the master PIN.
+  unlockSeat: (id, pin) => load().then((s) => s.unlockSeat(id, pin)),
+  verifyHostPin: (id, pin) => load().then((s) => s.verifyHostPin(id, pin)),
+  hostAction: (id, pin, action, targetSeat) => load().then((s) => s.hostAction(id, pin, action, targetSeat)),
   // events must return the unsubscribe synchronously (the screen subscribes in onMount), so it wires
   // the real subscription once the engine loads and, until then, cancels a pending subscribe.
   events: (id, onEvent) => {
@@ -54,7 +59,8 @@ export const localSource = {
       unsub();
     };
   },
-} satisfies GameLoopSource & Pick<LocalSource, 'events' | 'create' | 'list' | 'delete'>;
+} satisfies GameLoopSource &
+  Pick<LocalSource, 'events' | 'create' | 'list' | 'delete' | 'unlockSeat' | 'verifyHostPin' | 'hostAction'>;
 
 /**
  * gameSource returns the source that runs the game with the given id: the local engine for a local

ui/src/lib/i18n/en.ts

@@ -408,6 +408,16 @@ export const en = {
   'hotseat.hostPlaysTitle': 'Are you playing too?',
   'hotseat.hostPlaysYes': 'Yes, I play',
   'hotseat.hostPlaysNo': 'No',
+  'hotseat.unlock': 'Unlock',
+  'hotseat.unlockTitle': 'Unlock: {name}',
+  'hotseat.turnOf': 'Turn: {name}',
+  'hotseat.host': 'Host',
+  'hotseat.skip': 'Skip the current turn',
+  'hotseat.exclude': 'Exclude a player:',
+  'hotseat.terminate': 'End the game',
+  'hotseat.askSkip': "Skip {name}'s turn?",
+  'hotseat.askExclude': 'Remove {name} from the game?',
+  'hotseat.askTerminate': 'End the game with no result?',
 } as const;
 
 export type MessageKey = keyof typeof en;

ui/src/lib/i18n/ru.ts

@@ -408,4 +408,14 @@ export const ru: Record<MessageKey, string> = {
   'hotseat.hostPlaysTitle': 'Принимаете участие в игре?',
   'hotseat.hostPlaysYes': 'Да, играю',
   'hotseat.hostPlaysNo': 'Нет',
+  'hotseat.unlock': 'Разблокировать',
+  'hotseat.unlockTitle': 'Разблокировать: {name}',
+  'hotseat.turnOf': 'Ход: {name}',
+  'hotseat.host': 'Ведущий',
+  'hotseat.skip': 'Пропустить ход',
+  'hotseat.exclude': 'Исключить игрока:',
+  'hotseat.terminate': 'Отменить партию',
+  'hotseat.askSkip': 'Пропустить ход игрока {name}?',
+  'hotseat.askExclude': 'Удалить {name} из игры?',
+  'hotseat.askTerminate': 'Отменить партию без результата?',
 };