chore: claude settings

.gitignore

@@ -2,6 +2,12 @@
 .vscode/
 artifacts/.claude/scheduled_tasks.lock
 
+# Per-developer Claude Code overrides. The committed
+# `.claude/settings.json` holds the shared project defaults;
+# `settings.local.json` is each developer's local override
+# (looser permissions, disabled sandbox) and must not be staged.
+.claude/settings.local.json
+
 # Per-developer Vite dotenv overrides. The committed
 # `ui/frontend/.env.development` ships sane defaults for the
 # `tools/local-dev/` stack; `.local` siblings stay personal and