feat(messenger): wire the channel-roster import adapter seam

Phase D of channel-roster import. CrmMessagingAdapter.addMembers() proxies the
new crm.messenger.participant.addMany door action, enabling the SDK's '#' import
affordance in the channel/group settings panel. Pulls @insignia/iios-messaging-ui@0.1.8.

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": "^0.1.7",
+    "@insignia/iios-messaging-ui": "^0.1.8",
     "@photo-gallery/sdk": "file:./vendor/photo-gallery-sdk",
     "@tensorflow-models/coco-ssd": "^2.2.3",
     "@tensorflow/tfjs": "^4.22.0",