fix: Address code review findings for v2.4.0

- Fix 404 accepted as valid API response in config_flow validation (both ConfigFlow and OptionsFlow)
- Sanitize catch-all exception in config_flow (str(e) → "unknown" error key)
- Add exception chaining (from err) to ConfigEntryNotReady raise
- Replace datetime.now() with dt_util.utcnow() for HA timezone convention
- Add defensive raise after retry loop in api_client._make_request
- Remove unused CONF_API_KEY/CONF_NAME imports from const.py
- Restore google-genai dependency in manifest (required for Gemini provider)

custom_components/ha_text_ai/config_flow.py

@@ -306,7 +306,7 @@ class HATextAIConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
                     vol.Required(CONF_API_ENDPOINT, default=input_copy.get(CONF_API_ENDPOINT, get_default_endpoint(self._provider))): str,
                     # Other fields remain the same
                 }),
-                errors={"base": str(e)}
+                errors={"base": "unknown"}
             )
 
         # All validation passed, create the entry
@@ -378,7 +378,7 @@ class HATextAIConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
                     if response.status == 401:
                         self._errors["base"] = "invalid_auth"
                         return False
-                    elif response.status not in [200, 404]:
+                    elif response.status != 200:
                         self._errors["base"] = "cannot_connect"
                         return False
                     return True
@@ -514,7 +514,7 @@ class OptionsFlowHandler(config_entries.OptionsFlow):
                 if response.status == 401:
                     self._errors["base"] = "invalid_auth"
                     return False
-                elif response.status not in [200, 404]:
+                elif response.status != 200:
                     self._errors["base"] = "cannot_connect"
                     return False
                 return True