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/command-palette.tsx

@@ -76,7 +76,10 @@ export function CommandPaletteProvider({ children }: { children: ReactNode }) {
         // Filtered by role so reception can't jump to clinical pages, and by
         // the AI kill-switch so the disabled chat isn't listed.
         items: visibleNavItems(role)
-          .filter((item) => aiAllowed || item.id !== "new-chat")
+          .filter(
+            (item) =>
+              aiAllowed || (item.id !== "new-chat" && item.id !== "analysis"),
+          )
           .flatMap((item) =>
           item.subs?.length
             ? item.subs.map((sub) => ({