feat(P3.T7): RemoteRevokedScreen overlay for own-device revocation

apps/desktop/src/App.tsx

@@ -4,6 +4,7 @@ import { HashRouter, Navigate, Outlet, Route, Routes } from 'react-router-dom';
 import { AppShell } from './components/AppShell';
 import { CrashToast } from './components/CrashToast';
 import { ErrorBoundary } from './components/ErrorBoundary';
+import { RemoteRevokedScreen } from './components/RemoteRevokedScreen';
 import { SpinnerIcon } from './components/icons';
 import { UpdateToast } from './components/UpdateToast';
 import { RequireAdmin, RequireAuth, RequireDevice } from './components/guards';
@@ -168,6 +169,7 @@ export function App() {
                   </Routes>
                   <UpdateToast />
                   <CrashToast />
+                  <RemoteRevokedScreen />
                 </HashRouter>
               </CallProvider>
             </ConversationsProvider>

apps/desktop/src/components/RemoteRevokedScreen.tsx

@@ -0,0 +1,41 @@
+import { useTranslation } from 'react-i18next';
+
+import { useAuth } from '../context/AuthContext';
+
+export function RemoteRevokedScreen() {
+  const { t } = useTranslation();
+  const { revokedRemotely, acknowledgeRevocation } = useAuth();
+
+  if (!revokedRemotely) return null;
+
+  return (
+    <div
+      role="alertdialog"
+      aria-modal="true"
+      aria-labelledby="remote-revoked-title"
+      className="fixed inset-0 z-[1000] flex items-center justify-center bg-ink-950/95 p-6"
+    >
+      <div className="max-w-sm rounded-2xl border border-line bg-surface-2 p-6 text-center shadow-xl">
+        <h2
+          id="remote-revoked-title"
+          className="mb-2 font-display text-xl font-semibold text-fg"
+        >
+          {t('app:auth.revoked_title', { defaultValue: 'Du wurdest remote abgemeldet' })}
+        </h2>
+        <p className="mb-5 text-sm text-fg-muted">
+          {t('app:auth.revoked_body', {
+            defaultValue:
+              'Ein anderes deiner Geräte hat diesen Login beendet. Aus Sicherheitsgründen wurden alle lokalen Daten gelöscht.',
+          })}
+        </p>
+        <button
+          type="button"
+          onClick={acknowledgeRevocation}
+          className="inline-flex cursor-pointer items-center justify-center rounded-lg bg-accent px-4 py-2 text-sm font-semibold text-accent-fg transition hover:brightness-110 focus:outline-none focus-visible:ring-2 focus-visible:ring-accent/40"
+        >
+          {t('app:auth.revoked_acknowledge', { defaultValue: 'Verstanden' })}
+        </button>
+      </div>
+    </div>
+  );
+}