Safety screens: followers, blocking, reporting, admin

Web and mobile:
- Follower/following lists (tap the counts), with Follow buttons and
  "Remove" on your own followers.
- Profile ⋯ menu: block (with confirmation) / unblock, and report with a
  reason and optional note. "Follows you" label, "Follow back", and a
  banner on profiles you've blocked.
- Blocked accounts list in Settings, with unblock.
Web only: /admin for the admin account: stats, open/resolved reports,
resolve, suspend/unsuspend.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MzFywujuH9TiuXbr9vjoX8

apps/mobile/src/app/(tabs)/settings.tsx

@@ -441,6 +441,7 @@ function Account() {
       <Body muted style={styles.small}>
         Signed in as @{me?.username} · {me?.plan === 'free' ? 'Free plan' : 'Plus'}
       </Body>
+      <Button small title="Blocked accounts" onPress={() => router.push('/blocked')} style={{ alignSelf: 'flex-start' }} />
       <Row>
         <Button small title="Log out" onPress={signOut} />
         <Button small variant="danger" title="Delete account" onPress={confirmDelete} />