feat: TTLock — correct DLL flow with buildNo/floorNo per lock

Backend: room-locks now store/return build_no, floor_no (required by
CE_WriteCard). issue-card passes buildNo/floorNo to agent instead of
cardSectors/username/password. testApi route simplified (no OAuth).

Frontend: remove username/password fields (not needed), add buildNo/floorNo
fields to lock mapping form, show building/floor in lock list.

Migration 056: adds build_no, floor_no columns to room_lock_mappings.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/migrations/056_ttlock_build_floor.sql

@@ -0,0 +1,5 @@
+-- Add build_no and floor_no to room_lock_mappings
+-- Required by CE_WriteCard(hotelInfo, buildNo, floorNo, mac, endTime, allowLockOut)
+ALTER TABLE room_lock_mappings
+  ADD COLUMN IF NOT EXISTS build_no INTEGER NOT NULL DEFAULT 1,
+  ADD COLUMN IF NOT EXISTS floor_no INTEGER NOT NULL DEFAULT 1;