Add per-recipient cooldown to QuickChatExecution (#4012)

`QuickChatExecution` had no cooldown, allowing a player to spam
quick-chat intents and flood a recipient's chat UI. This could bury
incoming alliance request notifications, preventing them from being seen
or accepted.

This fix mirrors the existing emoji cooldown pattern:

- Added `quickChatCooldown()` to `Config` (default: 30 ticks / 3 seconds)
- Added `canSendQuickChat(recipient)` and `recordQuickChat(recipient)`
to `Player` / `PlayerImpl`, tracking outgoing chats per recipient
- `QuickChatExecution.tick()` now checks `canSendQuickChat` before
displaying and records before the display calls (so the cooldown is
always written even if display throws)

tests/QuickChat.test.ts

@@ -0,0 +1,85 @@
+import { QuickChatExecution } from "../src/core/execution/QuickChatExecution";
+import { Game, Player, PlayerType } from "../src/core/game/Game";
+import { playerInfo, setup } from "./util/Setup";
+
+let game: Game;
+let player1: Player;
+let player2: Player;
+let player3: Player;
+
+describe("QuickChat cooldown", () => {
+  beforeEach(async () => {
+    game = await setup("plains", {}, [
+      playerInfo("player1", PlayerType.Human),
+      playerInfo("player2", PlayerType.Human),
+      playerInfo("player3", PlayerType.Human),
+    ]);
+
+    player1 = game.player("player1");
+    player1.conquer(game.ref(0, 0));
+
+    player2 = game.player("player2");
+    player2.conquer(game.ref(0, 1));
+
+    player3 = game.player("player3");
+    player3.conquer(game.ref(0, 2));
+
+    while (game.inSpawnPhase()) {
+      game.executeNextTick();
+    }
+  });
+
+  // Helper: add an execution and advance two ticks so tick() actually runs.
+  // (addExecution → unInitExecs; first tick: init(); second tick: tick())
+  function sendQuickChat(sender: Player, recipient: Player) {
+    game.addExecution(
+      new QuickChatExecution(sender, recipient.id(), "greet.hello", undefined),
+    );
+    game.executeNextTick(); // init
+    game.executeNextTick(); // tick
+  }
+
+  test("first quick chat is sent", () => {
+    expect(player1.canSendQuickChat(player2)).toBe(true);
+    sendQuickChat(player1, player2);
+    expect(player1.canSendQuickChat(player2)).toBe(false);
+  });
+
+  test("second quick chat within cooldown is blocked", () => {
+    sendQuickChat(player1, player2);
+    expect(player1.canSendQuickChat(player2)).toBe(false);
+
+    // Even after the second attempt, cooldown persists
+    sendQuickChat(player1, player2);
+    expect(player1.canSendQuickChat(player2)).toBe(false);
+  });
+
+  test("quick chat is allowed again after cooldown expires", () => {
+    sendQuickChat(player1, player2);
+    expect(player1.canSendQuickChat(player2)).toBe(false);
+
+    // Advance past the cooldown (3 * 10 = 30 ticks)
+    const cooldown = game.config().quickChatCooldown();
+    for (let i = 0; i < cooldown; i++) {
+      game.executeNextTick();
+    }
+
+    expect(player1.canSendQuickChat(player2)).toBe(true);
+  });
+
+  test("cooldown is per-sender — different sender is not affected", () => {
+    sendQuickChat(player1, player2);
+    expect(player1.canSendQuickChat(player2)).toBe(false);
+
+    // player2 sending to player1 is independent
+    expect(player2.canSendQuickChat(player1)).toBe(true);
+  });
+
+  test("cooldown is per-recipient — same sender can still chat with a different recipient", () => {
+    sendQuickChat(player1, player2);
+    expect(player1.canSendQuickChat(player2)).toBe(false);
+
+    // player1 is on cooldown for player2 but not for player3
+    expect(player1.canSendQuickChat(player3)).toBe(true);
+  });
+});