feat(devices): Scan Now + Manual Add (IP option, MAC colon-mask) → 2.1.4

'Scan Now' triggers POST /api/devices/scan from the band header. '+ Add by MAC'
renamed '+ Manual Add' with an optional IP field (addBody/addManual accept ip)
and a MAC input that auto-inserts colons as you type. Frontend test 4/4; DB-backed
api/repo tests written (run with the suite — skipped locally to avoid colliding
with a concurrent test run on void_test).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

lib/api/routes/devices.js

@@ -70,6 +70,7 @@ router.patch('/:mac', requireOwner, validate({ params: macParam, body: patchBody
 
 const addBody = z.object({
   mac: z.string().regex(/^[0-9a-f]{2}(:[0-9a-f]{2}){5}$/i),
+  ip: z.string().regex(/^\d{1,3}(\.\d{1,3}){3}$/).optional(),
   name: z.string().max(120).optional(),
   grp: z.enum(['Smart Home', 'Entertainment', 'Personal', 'Network', 'Flagged']).optional(),
   vendor: z.string().max(120).optional()