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/ui.tsx

@@ -265,7 +265,7 @@ export function Modal({ open, onClose, title, subtitle, icon, children, footer,
 /* Toast                                                       */
 /* ---------------------------------------------------------- */
 
-type Toast = { id: number; tone: "success" | "info" | "error"; title: string; desc?: string };
+type Toast = { id: number; tone: "success" | "info" | "error"; title: string; desc?: string; onClick?: () => void };
 type ToastCtx = { push: (t: Omit<Toast, "id">) => void };
 const ToastContext = createContext<ToastCtx | null>(null);
 
@@ -288,9 +288,12 @@ export function ToastProvider({ children }: { children: ReactNode }) {
       {children}
       <div className="ds-toasts">
         {items.map((t) => (
-          <div key={t.id} className={`ds-toast tone-${t.tone}`}>
+          <div key={t.id} className={`ds-toast tone-${t.tone}${t.onClick ? " is-clickable" : ""}`}>
             <Icon name={t.tone === "success" ? "check-circle" : t.tone === "error" ? "alert" : "info"} size={18} />
-            <div className="ds-toast-body">
+            <div
+              className="ds-toast-body"
+              {...(t.onClick ? { role: "button", tabIndex: 0, onClick: () => { t.onClick?.(); setItems((s) => s.filter((x) => x.id !== t.id)); } } : {})}
+            >
               <div className="ds-toast-title">{t.title}</div>
               {t.desc && <div className="ds-toast-desc">{t.desc}</div>}
             </div>