Add deno.lock to .gitignore

Deno >=2.6 generates lockfile v5 which is incompatible with
supabase-edge-runtime (Deno 2.1.4), causing deployment failures.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: RusDyn

.gitignore

@@ -3,6 +3,9 @@
 # MCP config (contains agent key secrets)
 .mcp.json
 
+# Deno lockfile (v5 incompatible with supabase-edge-runtime)
+deno.lock
+
 # dependencies
 /node_modules
 /.pnp