refactor: make game host return the setup promise

tests/core/game-host.test.ts

@@ -150,7 +150,7 @@ describe('GameHost', () => {
             const newPromptPromise = waitForPromptEvent(host);
             
             // Reset - should reset state and start new game
-            await host.setup('setup');
+            host.setup('setup');
 
             // State should be back to initial
             expect(host.context._state.value.currentPlayer).toBe('X');
@@ -173,7 +173,7 @@ describe('GameHost', () => {
             await promptPromise;
 
             // Setup should cancel the active prompt and reset state
-            await host.setup('setup');
+            host.setup('setup');
 
             // The original runPromise should be rejected due to cancellation
             try {
@@ -188,11 +188,11 @@ describe('GameHost', () => {
             expect(host.context._state.value.turn).toBe(0);
         });
 
-        it('should throw error when disposed', async () => {
+        it('should throw error when disposed', () => {
             const { host } = createTestHost();
             host.dispose();
 
-            await expect(host.setup('setup')).rejects.toThrow('GameHost is disposed');
+            expect(() => host.setup('setup')).toThrow('GameHost is disposed');
         });
     });
 
@@ -245,7 +245,7 @@ describe('GameHost', () => {
             const promptPromise = waitForPromptEvent(host);
 
             // Initial setup via reset
-            await host.setup('setup');
+            host.setup('setup');
             expect(setupCount).toBe(1);
 
             // State should be running