chore: drop private fly config gitignore entries, restore model_config.toml example

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: enriquephl

.gitignore

@@ -16,8 +16,4 @@ Cargo.lock.bak
 docs/superpowers/plans/
 
 # Supabase CLI scratch state (created by `supabase link`).
-**/supabase/.temp/
-
-examples/model_config.toml
-fly.toml
-docker/Dockerfile.fly
+**/supabase/.temp/