chore: ignore local Codex workflow files (#179)

* chore: add repository contributor guide

* chore: remove contributor guide draft

Author: itsDNNS

.gitignore

@@ -33,9 +33,13 @@ mockup*.png
 
 # GSD planning (local only)
 .planning/
+.codex/
+CLAUDE.md
+AGENTS.md.export*
 
 # Internal task tracking (local only)
 tasks/
 
 # E2E test screenshots (generated, local only)
 tests/e2e/screenshots/
+