imp: .env.example ai comment improvement

Author: ashconnell

.env.example

@@ -46,8 +46,15 @@ LIVEKIT_API_KEY=
 LIVEKIT_API_SECRET=
 
 
+##
 # AI
-AI_PROVIDER=anthropic # anthropic|openai|xai
-AI_MODEL=claude-sonnet-4-20250514 # claude-opus-4-1-20250805|claude-sonnet-4-20250514|gpt-5|gpt-5-mini|gpt-5-nano|grok-4-0709
-AI_EFFORT=medium # minimal|low|medium|high (OpenAI only, ignored for Anthropic)
+# --
+# AI_PROVIDER: openai, anthropic, xai
+# AI_MODEL: claude-opus-4-1-20250805, claude-sonnet-4-20250514, gpt-5, gpt-5-mini, gpt-5-nano, grok-4-0709
+# AI_EFFORT: minimal, low, medium, high (OpenAI only)
+# AI_API_KEY: The api key for the selected provider
+##
+AI_PROVIDER=anthropic
+AI_MODEL=claude-sonnet-4-20250514
+AI_EFFORT=medium
 AI_API_KEY=