- Remove unreachable `&& !xsrfToken` condition from `handleFetch` guard;
simplify the redundant `cookieParts.length > 0` check that follows it
- Add `TOO_MANY_LOGIN_ATTEMPTS` to both Error Handling sections in CLAUDE.md
(backend and frontend) so LLMs are aware of the code without looking it up
- Add reverse-proxy IP trust and IPv6 address-cycling caveats to ADR-022
Consequences section
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Documents the double-submit cookie CSRF pattern, sequential token-bucket
rate limiter with refund mechanic, and session revocation on password
change/reset — all implemented as part of issue #524.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>