feat(llm-config): complete migration of useGlobalLLMConfigs to globalLLMConfigsAtom

- Removed unused import from model-config-manager.tsx
- Deleted useGlobalLLMConfigs hook (no longer used anywhere)
- All 5 components now using jotai + tanstack query pattern
- Full backward compatibility maintained

surfsense_web/hooks/use-llm-configs.ts

@@ -135,43 +135,3 @@ export function useLLMPreferences(searchSpaceId: number | null) {
 		isOnboardingComplete,
 	};
 }
-
-export function useGlobalLLMConfigs() {
-	const [globalConfigs, setGlobalConfigs] = useState<LLMConfig[]>([]);
-	const [loading, setLoading] = useState(true);
-	const [error, setError] = useState<string | null>(null);
-
-	const fetchGlobalConfigs = async () => {
-		try {
-			setLoading(true);
-			const response = await authenticatedFetch(
-				`${process.env.NEXT_PUBLIC_FASTAPI_BACKEND_URL}/api/v1/global-llm-configs`,
-				{ method: "GET" }
-			);
-
-			if (!response.ok) {
-				throw new Error("Failed to fetch global LLM configurations");
-			}
-
-			const data = await response.json();
-			setGlobalConfigs(data);
-			setError(null);
-		} catch (err: any) {
-			setError(err.message || "Failed to fetch global LLM configurations");
-			console.error("Error fetching global LLM configurations:", err);
-		} finally {
-			setLoading(false);
-		}
-	};
-
-	useEffect(() => {
-		fetchGlobalConfigs();
-	}, []);
-
-	return {
-		globalConfigs,
-		loading,
-		error,
-		refreshGlobalConfigs: fetchGlobalConfigs,
-	};
-}