perf(ui): non-blocking model and tool server loading for unreachable connections (#26289)

- Move setModels() and setToolServers() out of the loaded gate in
  +layout.svelte so the page renders immediately instead of blocking
  behind slow/unreachable connection timeouts
- Track failed Ollama backend URLs from /api/tags and skip them in the
  subsequent /api/ps fan-out, eliminating a redundant second timeout
- Silence the autocomplete toast that fires during the transient empty
  model state

src/lib/components/chat/MessageInput.svelte

@@ -1545,7 +1545,7 @@
 														($settings?.promptAutocomplete ?? false)}
 													generateAutoCompletion={async (text) => {
 														if (selectedModelIds.length === 0 || !selectedModelIds.at(0)) {
-															toast.error($i18n.t('Please select a model first.'));
+															return null;
 														}
 
 														const res = await generateAutoCompletion(

src/routes/(app)/+layout.svelte

@@ -87,7 +87,7 @@
 		}
 	};
 
-	const setUserSettings = async (cb: () => Promise<void>) => {
+	const setUserSettings = async (cb?: () => Promise<void>) => {
 		let userSettings = await getUserSettings(localStorage.token).catch((error) => {
 			console.error(error);
 			return null;
@@ -209,14 +209,15 @@
 			checkLocalDBChats(),
 			setBanners().catch((e) => console.error('Failed to load banners:', e)),
 			setTools().catch((e) => console.error('Failed to load tools:', e)),
-			setUserSettings(async () => {
-				await Promise.all([
-					setModels().catch((e) => console.error('Failed to load models:', e)),
-					setToolServers().catch((e) => console.error('Failed to load tool servers:', e))
-				]);
-			}).catch((e) => console.error('Failed to load user settings:', e))
+			setUserSettings().catch((e) => console.error('Failed to load user settings:', e))
 		]);
 
+		// Load models and tool servers in the background — don't block page render.
+		// These contact external services (Ollama, OpenAI, tool servers, terminal
+		// servers) that may be slow or unreachable.
+		setModels().catch((e) => console.error('Failed to load models:', e));
+		setToolServers().catch((e) => console.error('Failed to load tool servers:', e));
+
 		// Helper function to check if the pressed keys match the shortcut definition
 		const isShortcutMatch = (event: KeyboardEvent, shortcut): boolean => {
 			const keys = shortcut?.keys || [];