Three security issues found during review:
1. password_hash exposed via GET /api/settings
load_settings() returned all fields including the stored hash.
Fix: strip password_hash from the response in routes.py.
2. password_hash directly settable via POST /api/settings
'password_hash' was in _SETTINGS_ALLOWED_KEYS, so an attacker
could POST {password_hash: 'X'} to hijack auth without knowing
the current password.
Fix: exclude password_hash from _SETTINGS_ALLOWED_KEYS.
(Use _set_password for the legitimate hash-and-store path.)
3. Security headers missing from /api/auth/login and /api/auth/logout
These endpoints built their responses manually (bypassing j()),
so they omitted X-Content-Type-Options etc.
Fix: call _security_headers() before end_headers() on both.
Tests updated: renamed test to assert key absent (not just None),
added new test verifying direct password_hash POST is blocked.
3c95502979