gitignore: add _get_id.py and AGENTS.md, untrack AGENTS.md

.gitignore

@@ -15,5 +15,10 @@ __pycache__/
 ssh_update.py
 ssh_*.py
 blue_archive/ba_students.json
+_get_id.py
+AGENTS.md
 firebase-service-account.json
 firebase_service_account.json
+**/.codewhale/*
+!**/.codewhale/constitution.json
+.deepseek/