Update backend.py

backend.py

@@ -51,10 +51,10 @@ def get_project(project_id): return _db_execute("SELECT * FROM projects WHERE id
 
 # ------------------------------ MODEL LOADING & CACHING ------------------------------
 MODEL_REGISTRY = {
-    "ceo": "microsoft/Phi-3-mini-4k-instruct",
-    "manager": "Qwen/Qwen2-1.5B-Instruct",
-    "worker_coder": "Qwen/Qwen2-0.5B-Instruct",
-    "worker_tester": "Qwen/Qwen2-0.5B-Instruct",
+    "ceo": "Qwen/Qwen3-0.6B",
+    "manager": "Qwen/Qwen3-0.6B",
+    "worker_coder": "Qwen/Qwen3-0.6B",
+    "worker_tester": "Qwen/Qwen3-0.6B",
 }
 _MODEL_CACHE = {}