- Extract KEBAB_RE, SESSION_COOKIE, SESSION_MAX_AGE_MS, COOKIE_MAX_AGE,
authRequest(), and sessionResponse() to auth.ts — eliminating 4 copies
of the auth() wrapper and 3 copies of KEBAB_RE across admin API routes
- Remove timing side-channel: drop a.length !== b.length early-return
before timingSafeEqual in verifySession (SHA-256 HMAC always 64 chars)
- Fix YOLO localStorage write-before-read race using initialization guard
- Fix admin layout /api/ bypass to return {} instead of {authenticated:true}
- Extract extractError() helper in admin page — removes 4 inline patterns
- Parallel Promise.all in admin loadData() — halves round-trip latency
- Parallel Promise.all in moveCheckedUnits() + surface per-request errors
- Hoist Big(inputValue) above .map() in converter — one alloc per recompute
- O(n) single-pass orderedResults using Map instead of O(n*groups) filters
- Fix expandedGroups.add() mutation — use Set assignment for consistency
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Implements full admin interface for managing units and groups.
Migrates converter from static imports to server-side data loading.
- Switch adapter-static → adapter-node
- Add bcryptjs session auth with HMAC-signed cookies
- Add data/units.json and data/config.json data layer
- Add atomic file writes via temp-file rename
- Add public GET /api/units endpoint
- Add auth-gated admin CRUD API for units and groups
- Add two-panel admin UI with group tree and edit forms
- Add YOLO mode toggle for cross-group conversions
- Add visual group dividers in converter results grid
- Update ResultItem type for nullable convertedValue and isYolo flag
- Group deletion supports reassign/orphan with toBase recalculation
Rollback point: 067fd44
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>