Fix model selection resetting issue

The useEffect was re-running every time model changed, causing
Claude model selection to reset back to Ollama models. Fixed by:
- Removing model from useEffect dependency array
- Only run model fetch on component mount
- Check if saved model exists before loading it
- Don't reset model if it's not in Ollama list (allows Claude)

src/components/Chat.tsx

@@ -102,9 +102,9 @@ export function Chat({ projectPath, onCloseProject }: ChatProps) {
 						const savedModel = await invoke<string | null>(
 							"get_model_preference",
 						);
-						if (savedModel && models.includes(savedModel)) {
+						if (savedModel) {
 							setModel(savedModel);
-						} else if (!models.includes(model)) {
+						} else if (models.length > 0) {
 							setModel(models[0]);
 						}
 					} catch (e) {
@@ -114,7 +114,7 @@ export function Chat({ projectPath, onCloseProject }: ChatProps) {
 			})
 			.catch((err) => console.error(err));
 		// eslint-disable-next-line react-hooks/exhaustive-deps
-	}, [model]);
+	}, []);
 
 	useEffect(() => {
 		const unlistenUpdatePromise = listen<Message[]>("chat:update", (event) => {