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>

src/components/dashboard/dashboard.tsx

@@ -18,6 +18,8 @@ import { TeamManagement } from "./team-management";
 import { MessengerSdk } from "./messenger-sdk";
 import { InboxSdk } from "./inbox-sdk";
 import { Settings } from "./settings";
+import { NotificationCenter } from "./notification-center";
+import { RealtimeProvider } from "@/lib/realtime";
 import { SmartGallery } from "./smart-gallery";
 import "../../app/dashboard/dashboard.css";
 
@@ -47,11 +49,13 @@ export function Dashboard() {
 
   return (
     <div className="dash-root" data-theme={theme}>
+      <RealtimeProvider>
       <Sidebar active={active} onSelect={setActive} />
       <div className="dash-main">
         <Topbar theme={theme} onToggle={toggle} title={title} subtitle={subtitle} onNavigate={navigateToConversation} />
         <div className="dash-content">
           <ToastProvider>
+            <NotificationCenter active={active} onNavigate={navigateToConversation} />
             {active === "profile" ? <Profile />
               : active === "support" ? <Support />
               : active === "rules" ? <Rules />
@@ -65,6 +69,7 @@ export function Dashboard() {
           </ToastProvider>
         </div>
       </div>
+      </RealtimeProvider>
     </div>
   );
 }