fix: relax conversational guard on long/detailed messages over 60 chars to allow prompt tool execution

vibn-frontend/app/api/chat/route.ts

@@ -763,6 +763,7 @@ export async function POST(request: Request) {
       // This is more reliable than a prompt rule against a "do-er" model.
       function isConversational(msg: string): boolean {
         const m = msg.trim();
+        if (m.length > 60) return false; // Long/detailed messages are action statements or bug reports, not simple chit-chat
         if (m.length < 3) return true; // single word / emoji
         if (m.endsWith("?")) return true; // explicit question
         // Short phrases that are status checks or greetings