fix(social): robot blocks

Blocking an auto-match opponent who is secretly a pooled robot is recorded  instead in a separate `robot_blocks` table.

Now blocking behaves the same in that game (struck name, hidden composer) and lists the blocked opponent under the name you saw, but is recorded only against that game — the disguise holds, the shared robot is never globally blocked, and the matchmaker keeps pairing you with robots (so you can never block yourself out of opponents).

- the shared robot account is never put in `blocks`
- the matchmaker keeps it free and it is not blocked under its other per-game names
- the blocked list and the in-game card still show it by joining that table; an unblock deletes the row

ui/src/lib/client.ts

@@ -6,6 +6,7 @@
 
 import type {
   AccountRef,
+  BlockList,
   BlockStatus,
   ChatMessage,
   EvalResult,
@@ -127,8 +128,8 @@ export interface GatewayClient {
   friendCodeRedeem(code: string): Promise<AccountRef>;
 
   // --- blocks ---
-  blocksList(): Promise<AccountRef[]>;
-  block(accountId: string): Promise<void>;
+  blocksList(): Promise<BlockList>;
+  block(accountId: string, gameId?: string): Promise<void>;
   unblock(accountId: string): Promise<void>;
 
   // --- invitations ---

ui/src/lib/codec.ts

@@ -9,6 +9,8 @@ import { indexForLetter, letterForIndex, setAlphabet, type AlphabetEntryWire } f
 import type { PlacedTile } from './client';
 import type {
   AccountRef,
+  BlockList,
+  RobotBlockEntry,
   Banner,
   BannerCampaign,
   BestMove,
@@ -576,11 +578,15 @@ export function decodeEvent(kind: string, payload: Uint8Array): PushEvent | null
 
 // --- social encoders ---
 
-export function encodeTarget(accountId: string): Uint8Array {
+export function encodeTarget(accountId: string, gameId?: string): Uint8Array {
   const b = new Builder(64);
   const id = b.createString(accountId);
+  // game_id is set only by an in-game block, so a disguised-robot opponent is recorded
+  // per-game; every other target path omits it.
+  const gid = gameId ? b.createString(gameId) : 0;
   fb.TargetRequest.startTargetRequest(b);
   fb.TargetRequest.addAccountId(b, id);
+  if (gid) fb.TargetRequest.addGameId(b, gid);
   return finish(b, fb.TargetRequest.endTargetRequest(b));
 }
 
@@ -722,14 +728,25 @@ export function decodeOutgoingList(buf: Uint8Array): AccountRef[] {
   return out;
 }
 
-export function decodeBlockList(buf: Uint8Array): AccountRef[] {
+export function decodeBlockList(buf: Uint8Array): BlockList {
   const l = fb.BlockList.getRootAsBlockList(new ByteBuffer(buf));
-  const out: AccountRef[] = [];
+  const blocked: AccountRef[] = [];
   for (let i = 0; i < l.blockedLength(); i++) {
     const r = l.blocked(i);
-    if (r) out.push(decodeAccountRef(r));
+    if (r) blocked.push(decodeAccountRef(r));
   }
-  return out;
+  const robots: RobotBlockEntry[] = [];
+  for (let i = 0; i < l.robotsLength(); i++) {
+    const r = l.robots(i);
+    if (r)
+      robots.push({
+        id: r.id() ?? '',
+        displayName: r.displayName() ?? '',
+        gameId: r.gameId() ?? '',
+        seat: r.seat(),
+      });
+  }
+  return { blocked, robots };
 }
 
 export function decodeFriendCode(buf: Uint8Array): FriendCode {

ui/src/lib/mock/client.ts

@@ -13,6 +13,7 @@ import type {
 import { GatewayError } from '../client';
 import type {
   AccountRef,
+  BlockList,
   BlockStatus,
   ChatMessage,
   EvalResult,
@@ -555,10 +556,13 @@ export class MockGateway implements GatewayClient {
   }
 
   // --- blocks ---
-  async blocksList(): Promise<AccountRef[]> {
-    return this.blocks.map((b) => ({ ...b }));
+  async blocksList(): Promise<BlockList> {
+    // The mock models human blocks only (no disguised robots); robots stays empty.
+    return { blocked: this.blocks.map((b) => ({ ...b })), robots: [] };
   }
-  async block(accountId: string): Promise<void> {
+  async block(accountId: string, _gameId?: string): Promise<void> {
+    // A block hides the blocked person from the blocker's own friends list (the real
+    // ListFriends filters them out), without deleting the underlying friendship.
     this.friends = this.friends.filter((f) => f.accountId !== accountId);
     if (!this.blocks.some((b) => b.accountId === accountId)) {
       this.blocks.push({ accountId, displayName: this.nameFor(accountId) });

ui/src/lib/model.ts

@@ -205,6 +205,22 @@ export interface AccountRef {
   displayName: string;
 }
 
+// RobotBlockEntry is one blocked disguised-robot opponent: a per-game record (not a real
+// account) carrying the game name the player saw and the game/seat it was blocked in. Its id
+// is used to unblock it.
+export interface RobotBlockEntry {
+  id: string;
+  displayName: string;
+  gameId: string;
+  seat: number;
+}
+
+// BlockList is the caller's blocked humans plus the per-game disguised-robot blocks.
+export interface BlockList {
+  blocked: AccountRef[];
+  robots: RobotBlockEntry[];
+}
+
 /** A freshly issued one-time friend code (the plaintext is returned once). */
 export interface FriendCode {
   code: string;

ui/src/lib/transport.ts

@@ -187,8 +187,8 @@ export function createTransport(baseUrl: string): GatewayClient {
     async blocksList() {
       return codec.decodeBlockList(await exec('blocks.list', codec.empty()));
     },
-    async block(accountId) {
-      await exec('blocks.add', codec.encodeTarget(accountId));
+    async block(accountId, gameId) {
+      await exec('blocks.add', codec.encodeTarget(accountId, gameId));
     },
     async unblock(accountId) {
       await exec('blocks.remove', codec.encodeTarget(accountId));