test(01-08): add GameEventStore behavior regression

- Covers public-barrel add/get and unknown-id behavior
- Verifies duplicate warning code and last-write-wins behavior

packages-user/data-common/src/store/eventStore.test.ts

@@ -0,0 +1,76 @@
+import { AnonTokyoInterpreter } from 'anon-tokyo';
+import {
+    afterAll,
+    afterEach,
+    beforeAll,
+    describe,
+    expect,
+    it,
+    vi
+} from 'vitest';
+
+interface TestModules {
+    GameEvent: typeof import('@user/data-common').GameEvent;
+    GameEventStore: typeof import('@user/data-common').GameEventStore;
+    logger: typeof import('@motajs/common').logger;
+}
+
+let modules: TestModules;
+
+beforeAll(async () => {
+    vi.stubGlobal('main', { replayChecking: true });
+    vi.stubGlobal('location', { origin: 'http://localhost' });
+    const commonModule = await import('@user/data-common');
+    const loggerModule = await import('@motajs/common');
+    modules = {
+        GameEvent: commonModule.GameEvent,
+        GameEventStore: commonModule.GameEventStore,
+        logger: loggerModule.logger
+    };
+});
+
+afterEach(() => {
+    vi.restoreAllMocks();
+});
+
+afterAll(() => {
+    vi.unstubAllGlobals();
+});
+
+function createEvent() {
+    const interpreter = new AnonTokyoInterpreter({
+        builtInFunctions: [],
+        globalFunctions: []
+    });
+    return new modules.GameEvent(interpreter, []);
+}
+
+describe('GameEventStore public barrel behavior', () => {
+    it('retrieves an event by the id used when adding it', () => {
+        const store = new modules.GameEventStore();
+        const event = createEvent();
+
+        store.addEvent('event-id', event);
+
+        expect(store.getEvent('event-id')).toBe(event);
+    });
+
+    it('returns null for an unknown id', () => {
+        const store = new modules.GameEventStore();
+
+        expect(store.getEvent('missing-id')).toBeNull();
+    });
+
+    it('warns and overwrites when an id is added twice', () => {
+        const store = new modules.GameEventStore();
+        const firstEvent = createEvent();
+        const secondEvent = createEvent();
+        const warning = vi.spyOn(modules.logger, 'warn');
+
+        store.addEvent('duplicate-id', firstEvent);
+        store.addEvent('duplicate-id', secondEvent);
+
+        expect(warning).toHaveBeenCalledWith(170, 'duplicate-id');
+        expect(store.getEvent('duplicate-id')).toBe(secondEvent);
+    });
+});