Stage 17 round 6 (#16/#17, PR C): lobby sort + server-derived in-game friend state

Lobby: group the my-games list into your-turn / opponent-turn / finished
(empty sections hidden), ordered by last activity (your-turn oldest-first,
the other two newest-first), as a compact line-separated list. gameDTO and
FB GameView gain last_activity_unix (turn start while active, finish time
once finished); a pure lib/lobbysort.ts holds the grouping/ordering.

Friends: the in-game 'add to friends' item is now server-derived via a new
GET /user/friends/outgoing (+ friends.outgoing op), returning addressees with
a pending OR declined request (both read as 'request sent'), so it is correct
across reloads; it shows a disabled '✓ in friends' once accepted. It
live-updates when the opponent answers: RespondFriendRequest now publishes
friend_added (accept) / friend_declined (new notify sub-kind, decline) to the
original requester, whose open game re-derives its friend state.

Tests: lobbysort unit test; gateway outgoing + last_activity transcode tests;
backend integration ListOutgoingRequests + respond-publishes-to-requester;
e2e updated for the new lobby section labels + a non-friend active opponent.
Docs: ARCHITECTURE notify catalog, FUNCTIONAL(+ru) lobby/friends, PLAN.

PLAN.md

@@ -1355,11 +1355,29 @@ provided cert) at the contour caddy; prod VPN; rollback.
     and a ☼/☾ theme toggle that is **ephemeral** (follows the system scheme, never persisted, no "auto").
     The "Play in browser" CTA was dropped (no standalone-web onboarding yet).
   - **Game/Telegram review-pass polish:** the USSR flag emblem redrawn (canonical hammer & sickle,
-    scaled down ×1.5 below the star); touch drag enlarges the drag ghost ×1.5 (touch only — the
-    finger hides the tile) and suppresses the iOS tap-highlight that lingered on a rack tile sliding
-    into a dragged tile's slot; and **Telegram fullscreen** no longer hides our header under its
-    native nav — the header drops below the content-safe-area top inset and the menu (hamburger)
-    lifts into the nav band, centred (`--tg-content-top` from the SDK + a `tg-fullscreen` class).
+    scaled down ×1.5 below the star, the star itself +25%); touch drag enlarges the drag ghost ×1.5
+    (touch only — the finger hides the tile) and suppresses the iOS tap-highlight that lingered on a
+    rack tile sliding into a dragged tile's slot; a placed tile can be **dragged to another board
+    cell** (it lifts off its origin for the drag, and `touch-action:none` lets the drag win over the
+    board pan when zoomed) and the manual-select ring clears when a tile is recalled; and **Telegram
+    fullscreen** no longer hides our header under its native nav — the whole header drops below the
+    content-safe-area top inset (title and the right-aligned menu both clear the nav), via
+    `--tg-content-top` from the SDK + a `tg-fullscreen` class. (Telegram's Mini App SDK exposes no way
+    to set the native nav-bar title, move its buttons, or add items to its "⋯" menu, so we keep our
+    own header and simply push it clear.)
+  - **Lobby sort + in-game friend state (review pass, PR C):** the **my-games** lobby now groups games
+    into *your turn* / *opponent's turn* / *finished* (empty sections hidden) and orders them by last
+    activity — your-turn oldest-first (the longest-waiting on top), the other two newest-first — in a
+    compact, line-separated list (the owner's density pick over bordered cards). `gameDTO` / FB
+    `GameView` gained `last_activity_unix` (the turn start while active, the finish time once
+    finished). The in-game **"add to friends"** item is now **server-derived** (new `GET
+    /user/friends/outgoing` + `friends.outgoing` op, returning the addressees already requested —
+    pending **or** declined, which both read as "request sent") so it is correct across reloads, shows
+    a disabled **"✓ in friends"** once accepted, and **live-updates** when the opponent answers:
+    `RespondFriendRequest` now publishes `friend_added` (accept) / `friend_declined` (a new notify
+    sub-kind, decline) to the **original requester**, whose open game re-derives its friend state.
+    Owner decisions: a declined request stays "request sent" (non-revealing); an accepted opponent
+    reads "✓ in friends"; rack-tile reorder while tiles are placed stays disabled by design.
 
 ## Deferred TODOs (cross-stage)