ui: Refactor models store, MCP service, and gate logs behind VITE_DEBUG (#23236)

* refactor: Scope console logs to `DEV` + `VITE_DEBUG` env vars

* refactor: skip MCP proxy probe when no server requires it

* refactor: suppress expected disconnect errors during MCP client shutdown

* refactor: Deduplicate requests

* refactor: deduplicate model fetching across ROUTER and MODEL modes

* refactor: Clean up models logic

* chore: Add `.env.example` file

* refactor: replace client-side CORS proxy probe with server status flag

* refactor: Post-review fixes

* test: add vitest client setup with API fetch mocks

tools/ui/src/lib/utils/api-key-validation.ts

@@ -12,17 +12,21 @@ export async function validateApiKey(fetch: typeof globalThis.fetch): Promise<vo
 		return;
 	}
 
+	const apiKey = config().apiKey;
+
+	// No API key configured — server doesn't require auth, skip the request entirely.
+	// The /props endpoint is only protected when the server has API keys configured,
+	// and in that case the client always has one set (from settings).
+	if (!apiKey) {
+		return;
+	}
+
 	try {
-		const apiKey = config().apiKey;
-
 		const headers: Record<string, string> = {
-			'Content-Type': 'application/json'
+			'Content-Type': 'application/json',
+			Authorization: `Bearer ${apiKey}`
 		};
 
-		if (apiKey) {
-			headers.Authorization = `Bearer ${apiKey}`;
-		}
-
 		const response = await fetch(`${base}/props`, { headers });
 
 		if (!response.ok) {

tools/ui/src/lib/utils/legacy-migration.ts

@@ -333,7 +333,8 @@ async function migrateConversation(convId: string): Promise<number> {
 export async function runLegacyMigration(): Promise<void> {
 	if (!isMigrationNeeded()) return;
 
-	console.log('[Migration] Starting legacy message format migration...');
+	if (import.meta.env.DEV && import.meta.env.VITE_DEBUG)
+		console.log('[Migration] Starting legacy message format migration...');
 
 	try {
 		const conversations = await DatabaseService.getAllConversations();
@@ -344,12 +345,14 @@ export async function runLegacyMigration(): Promise<void> {
 			totalMigrated += count;
 		}
 
-		if (totalMigrated > 0) {
-			console.log(
-				`[Migration] Migrated ${totalMigrated} messages across ${conversations.length} conversations`
-			);
-		} else {
-			console.log('[Migration] No legacy messages found, marking as done');
+		if (import.meta.env.DEV && import.meta.env.VITE_DEBUG) {
+			if (totalMigrated > 0) {
+				console.log(
+					`[Migration] Migrated ${totalMigrated} messages across ${conversations.length} conversations`
+				);
+			} else {
+				console.log('[Migration] No legacy messages found, marking as done');
+			}
 		}
 
 		markMigrationDone();