feat(dashboard): live notifications phase 1 — presence, live unread, in-app toasts

Shared RealtimeProvider opens ONE dashboard-wide IIOS message socket reused by
the messenger tab and the new NotificationCenter. CrmMessagingAdapter gains
setFocus (drives presence/push suppression) and subscribeActivity (joins all
of the caller's threads, fans out incoming messages). NotificationCenter shows
a clickable toast on new messages when you're not on the messenger tab and
deep-links to the conversation. Pulls @insignia/iios-messaging-ui@0.1.7.

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

package.json

@@ -14,7 +14,7 @@
     "@huggingface/transformers": "^4.2.0",
     "@imgly/background-removal": "^1.7.0",
     "@insignia/iios-kernel-client": "^0.1.4",
-    "@insignia/iios-messaging-ui": "^0.1.6",
+    "@insignia/iios-messaging-ui": "^0.1.7",
     "@photo-gallery/sdk": "file:./vendor/photo-gallery-sdk",
     "@tensorflow-models/coco-ssd": "^2.2.3",
     "@tensorflow/tfjs": "^4.22.0",