fix(edge-functions): disable gateway JWT verification for llm-proxy

The Supabase gateway was validating JWTs before requests reached
the function. This caused "Invalid JWT" errors even for actions
that don't require authentication (like test_key).

The function now handles authentication internally, allowing
unauthenticated access to test_key while still requiring auth
for other actions.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: toto-castaldi

supabase/functions/llm-proxy/config.toml

@@ -0,0 +1,4 @@
+# Disable JWT verification at gateway level
+# The function handles authentication internally
+# This is needed because test_key action is called before user is fully authenticated
+verify_jwt = false