feat: TTLock encoder per workstation (Option A)

- Migration 051: add ttlock_com_port to workstations, drop com_port/workstation_id from hotel_ttlock_config
- Backend workstations PATCH: accepts ttlock_com_port alongside name
- Backend ttlock: test/issue-card use per-workstation com_port; auto-select online encoder if workstationId not specified
- TTLockPage Step 2: per-workstation table with COM port input, Save, Test buttons per row
- BookingDetailPanel: auto-issue if 1 encoder online, picker modal if multiple
- api.ts: TTLockConfig/Update cleaned up, Workstation gets ttlockComPort, issueCard/testEncoder updated

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

src/pages/EquipmentPage.tsx

@@ -647,7 +647,7 @@ function WorkstationCard({
 
   const saveName = async () => {
     if (!name.trim() || name === ws.name) { setEditing(false); return }
-    await api.workstations.update(slug, ws.id, name.trim())
+    await api.workstations.update(slug, ws.id, { name: name.trim() })
     setEditing(false)
     onRefresh()
   }