feat(config): support OPENROUTER_API_KEY, GROQ_API_KEY, and GEMINI_API_KEY loaded from .env

app/config.py

@@ -72,9 +72,12 @@ class Settings(BaseSettings):
     # Frontend Redirect
     FRONTEND_URL: str = "http://localhost:3000"
 
-    # OpenRouter/OpenAI fallback for local testing
+    # OpenRouter/OpenAI/Groq/Gemini API Keys
     OPENAI_API_KEY: str = ""
     OPENAI_BASE_URL: str = "https://openrouter.ai/api/v1"
+    OPENROUTER_API_KEY: str = ""
+    GROQ_API_KEY: str = ""
+    GEMINI_API_KEY: str = ""
 
     model_config = SettingsConfigDict(
         env_file=(".env", ENV_FILE_PATH),