Fix: Updated Groq model to llama-3.3-70b-versatile due to deprecation (Phase 9)

backend/services/config.py

@@ -56,7 +56,7 @@ class ConfigService:
 
     # Defaults used when DB has no config entry for a provider
     _DEFAULTS: Dict[str, Any] = {
-        "groq":        {"enabled": True,  "default_model": "llama3-70b-8192", "temperature": 0.7, "max_tokens": 4096},
+        "groq":        {"enabled": True,  "default_model": "llama-3.3-70b-versatile", "temperature": 0.7, "max_tokens": 4096},
         "openai":      {"enabled": True,  "default_model": "gpt-4o",                   "temperature": 0.7, "max_tokens": 4096},
         "openrouter":  {"enabled": True,  "default_model": "google/gemini-2.0-flash",  "temperature": 0.7, "max_tokens": 8192},
         "gemini":      {"enabled": True,  "default_model": "gemini-2.0-flash",         "temperature": 0.7, "max_tokens": 8192},