Rate limiting (closes the last security gap #3):
- New RateLimiter: in-memory fixed-window IP-based limiter (std::sync::Mutex
HashMap, no new deps). Configurable via RATE_LIMIT_MAX (default 100) +
RATE_LIMIT_WINDOW_SECS (default 60) env vars.
- general_rate_limit_middleware now reads ClientIp from request extensions and
rejects with 429 + Retry-After header when over the limit. Wired via
from_fn_with_state in app.rs. Lived on AppState as Arc<RateLimiter>.
- Deleted the dead auth_rate_limit_middleware (never wired).
- 3 unit tests (allows up to N, independent IPs, window reset).
E2E crypto lifecycle test:
- Full zero-knowledge round-trip against jsdom's real Web Crypto: setup →
encrypt → verify ciphertext → unlock with password → decrypt → recover via
phrase → rewrap under new password → decrypt. Plus wrong-password/wrong-phrase
failures and cross-user key isolation.
- Fixed wrapDek/unwrapDek: base64-encode raw DEK bytes (was using TextDecoder
which produced non-base64), and make unwrapped DEK extractable (needed for
rewrapDek to export).
Verified: backend 24 tests 0 warnings; frontend 24 tests, build clean.