frontend: make AI kill-switch a true clinic-wide master switch

The "Enable AI assistant" toggle already disabled the AI for everyone
(including owners/admins) at the policy layer, but the copy read as an
employee-only control and the Analysis surface stayed visible. Clarify
that the master switch covers admins too, and close the gaps: hide the
Analysis nav/command entry and redirect /analysis (alongside the chat
home) to /patients when AI is disabled. The employee-only toggle remains
the secondary option that keeps AI for owners/admins.

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

frontend/components/auth/app-auth-guard.tsx

@@ -56,9 +56,14 @@ export function AppAuthGuard({ children }: { children: ReactNode }) {
       router.replace(defaultLandingFor(role));
       return;
     }
-    // AI kill-switch: the chat home ("/") is off for this user — send them to
-    // patients (clinical roles always have it; non-clinical never land on "/").
-    if (!aiLoading && !aiAllowed && pathname === "/") {
+    // AI kill-switch: the AI surfaces — chat home ("/") and Analysis — are off
+    // for this user (a full clinic disable also covers owners/admins). Send them
+    // to patients (clinical roles always have it; non-clinical never land here).
+    if (
+      !aiLoading &&
+      !aiAllowed &&
+      (pathname === "/" || pathname === "/analysis")
+    ) {
       router.replace("/patients");
     }
   }, [ready, role, pathname, router, aiAllowed, aiLoading]);