fix(ai_client_stub): add module-level import for GeminiCliAdapter

The class was only accessible inside function scopes, causing
AttributeError when app_controller tried to instantiate it
at module level via ai_client.GeminiCliAdapter().

src/ai_client_proxy.py

@@ -42,6 +42,9 @@ class AIProxyClient:
                     continue
                 try:
                     response = json.loads(line)
+                    if response.get("type") == "ready" and self._status == "init":
+                        self._status = "ready"
+                        continue
                     rid = response.get("id")
                     if rid in self._pending:
                         self._pending[rid] = response