fix: address CodeRabbit feedback

- Sort .env.example model keys alphabetically.
- Narrow return type of create_demo() to gr.ChatInterface.
- Confirmed embedding model vars are already wired in src/utils/config.py.

.env.example

@@ -8,8 +8,8 @@ OPENAI_API_KEY=sk-your-key-here
 ANTHROPIC_API_KEY=sk-ant-your-key-here
 
 # Model names (optional - sensible defaults)
-OPENAI_MODEL=gpt-4-turbo
 ANTHROPIC_MODEL=claude-3-5-sonnet-20240620
+OPENAI_MODEL=gpt-4-turbo
 
 # ============== EMBEDDINGS ==============
 

src/app.py

@@ -186,7 +186,7 @@ async def research_agent(
         yield f"❌ **Error**: {e!s}"
 
 
-def create_demo() -> Any:
+def create_demo() -> gr.ChatInterface:
     """
     Create the Gradio demo interface with MCP support.