Implement donation troops/gold between human players after forming an alliance (#2450)

Resolves #2448 

Hi team,

I've implemented and locally tested the alliance-related changes
(including unit tests and some manual simulation with multiple browser
profiles).
Unfortunately I wasn't able to perform full end-to-end testing on the
live game server with two separate machines/accounts.

If someone on the team (or another contributor) can verify the alliance
flow with two real players, that would be greatly appreciated before
merging. Happy to hop on a call or provide any clarification needed.

Thanks!

## Description:

Fixed a race condition bug where donations (troops/gold) between human
players failed after forming an alliance. The issue was caused by a
one-tick delay in `AllianceRequestReplyExecution`: the alliance
acceptance logic ran in `tick()` instead of `init()`, meaning the
alliance wasn't created until the tick after the execution was added. If
a donation execution was added in the same turn as the alliance
acceptance, it would fail the `isFriendly()` check because the alliance
didn't exist yet.

**Root cause:** When human players formed alliances via reply, the
execution model delayed alliance creation by one tick, while bots called
`accept()` directly without this delay.

**Solution:** Moved alliance acceptance logic from `tick()` to `init()`
in `AllianceRequestReplyExecution.ts`, ensuring immediate alliance
creation and eliminating race conditions with donations.

**Changes:**
- Modified
`src/core/execution/alliance/AllianceRequestReplyExecution.ts` to
process alliance replies in `init()` instead of `tick()`
- Added comprehensive test suite `tests/AllianceDonation.test.ts` with 5
test cases covering donation scenarios after alliance formation (reply
and mutual request flows)
- All existing tests pass (323 total)

## Please complete the following:

- [x] I have added screenshots for all UI updates (N/A - backend logic
fix only)
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file (N/A - no user-facing text
changes)
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced


Discord: loacky
GitHub: @LoackyBit

---------

Co-authored-by: Evan <evanpelle@gmail.com>

src/core/execution/alliance/AllianceRequestReplyExecution.ts

@@ -19,12 +19,7 @@ export class AllianceRequestReplyExecution implements Execution {
       return;
     }
     this.requestor = mg.player(this.requestorID);
-  }
 
-  tick(ticks: number): void {
-    if (this.requestor === null) {
-      throw new Error("Not initialized");
-    }
     if (this.requestor.isFriendly(this.recipient)) {
       console.warn("already allied");
     } else {
@@ -46,6 +41,8 @@ export class AllianceRequestReplyExecution implements Execution {
     this.active = false;
   }
 
+  tick(ticks: number): void {}
+
   isActive(): boolean {
     return this.active;
   }

tests/AllianceDonation.test.ts

@@ -0,0 +1,139 @@
+import { AllianceRequestExecution } from "../src/core/execution/alliance/AllianceRequestExecution";
+import { AllianceRequestReplyExecution } from "../src/core/execution/alliance/AllianceRequestReplyExecution";
+import { DonateGoldExecution } from "../src/core/execution/DonateGoldExecution";
+import { Game, Player, PlayerType } from "../src/core/game/Game";
+import { playerInfo, setup } from "./util/Setup";
+
+let game: Game;
+let player1: Player;
+let player2: Player;
+
+describe("Alliance Donation", () => {
+  beforeEach(async () => {
+    game = await setup(
+      "plains",
+      {
+        infiniteGold: false,
+        instantBuild: true,
+        infiniteTroops: false,
+        donateGold: true,
+        donateTroops: true,
+      },
+      [
+        playerInfo("player1", PlayerType.Human),
+        playerInfo("player2", PlayerType.Human),
+      ],
+    );
+
+    player1 = game.player("player1");
+    player1.conquer(game.ref(0, 0));
+    player1.addGold(1000n);
+    player1.addTroops(1000);
+
+    player2 = game.player("player2");
+    player2.conquer(game.ref(0, 1));
+    player2.addGold(100n);
+    player2.addTroops(100);
+
+    while (game.inSpawnPhase()) {
+      game.executeNextTick();
+    }
+  });
+
+  test("Can donate gold after alliance formed by reply", () => {
+    game.addExecution(new AllianceRequestExecution(player1, player2.id()));
+    game.executeNextTick();
+
+    game.addExecution(
+      new AllianceRequestReplyExecution(player1.id(), player2, true),
+    );
+    game.executeNextTick();
+
+    expect(player1.isAlliedWith(player2)).toBeTruthy();
+    expect(player2.isAlliedWith(player1)).toBeTruthy();
+    expect(player1.isFriendly(player2)).toBeTruthy();
+    expect(player2.isFriendly(player1)).toBeTruthy();
+
+    expect(player1.canDonateGold(player2)).toBeTruthy();
+    const goldBefore = player2.gold();
+    const success = player1.donateGold(player2, 100n);
+    expect(success).toBeTruthy();
+    expect(player2.gold()).toBe(goldBefore + 100n);
+  });
+
+  test("Can donate troops after alliance formed by reply", () => {
+    game.addExecution(new AllianceRequestExecution(player1, player2.id()));
+    game.executeNextTick();
+
+    game.addExecution(
+      new AllianceRequestReplyExecution(player1.id(), player2, true),
+    );
+    game.executeNextTick();
+
+    expect(player1.isAlliedWith(player2)).toBeTruthy();
+    expect(player2.isAlliedWith(player1)).toBeTruthy();
+
+    expect(player1.canDonateTroops(player2)).toBeTruthy();
+    const troopsBefore = player2.troops();
+    const success = player1.donateTroops(player2, 100);
+    expect(success).toBeTruthy();
+    expect(player2.troops()).toBe(troopsBefore + 100);
+  });
+
+  test("Can donate gold after alliance formed by mutual request", () => {
+    game.addExecution(new AllianceRequestExecution(player1, player2.id()));
+    game.executeNextTick();
+
+    game.addExecution(new AllianceRequestExecution(player2, player1.id()));
+    game.executeNextTick();
+
+    expect(player1.isAlliedWith(player2)).toBeTruthy();
+    expect(player2.isAlliedWith(player1)).toBeTruthy();
+    expect(player1.isFriendly(player2)).toBeTruthy();
+    expect(player2.isFriendly(player1)).toBeTruthy();
+
+    expect(player1.canDonateGold(player2)).toBeTruthy();
+    const goldBefore = player2.gold();
+    const success = player1.donateGold(player2, 100n);
+    expect(success).toBeTruthy();
+    expect(player2.gold()).toBe(goldBefore + 100n);
+  });
+
+  test("Can donate troops after alliance formed by mutual request", () => {
+    game.addExecution(new AllianceRequestExecution(player1, player2.id()));
+    game.executeNextTick();
+
+    game.addExecution(new AllianceRequestExecution(player2, player1.id()));
+    game.executeNextTick();
+
+    expect(player1.isAlliedWith(player2)).toBeTruthy();
+    expect(player2.isAlliedWith(player1)).toBeTruthy();
+
+    expect(player1.canDonateTroops(player2)).toBeTruthy();
+    const troopsBefore = player2.troops();
+    const success = player1.donateTroops(player2, 100);
+    expect(success).toBeTruthy();
+    expect(player2.troops()).toBe(troopsBefore + 100);
+  });
+
+  test("Can donate immediately after accepting alliance (race condition)", () => {
+    game.addExecution(new AllianceRequestExecution(player1, player2.id()));
+    game.executeNextTick();
+
+    const goldBefore = player2.gold();
+    game.addExecution(
+      new AllianceRequestReplyExecution(player1.id(), player2, true),
+    );
+    game.addExecution(new DonateGoldExecution(player1, player2.id(), 100));
+
+    game.executeNextTick();
+
+    expect(player1.isAlliedWith(player2)).toBeTruthy();
+    expect(player2.isAlliedWith(player1)).toBeTruthy();
+
+    game.executeNextTick();
+
+    // Donation should have succeeded
+    expect(player2.gold()).toBe(goldBefore + 100n);
+  });
+});