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>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "void-server",
-  "version": "2.1.3",
+  "version": "2.1.4",
   "type": "module",
   "private": true,
   "scripts": {