[H-11] Moderation actions don't block self-targeting

Resolved.

Added self-targeting guards to all four moderation actions in src/Controllers/AdminModerationController.php:

• warn($id)
• suspend($id)
• ban($id)
• shadowBan($id)

Each now checks (int) $reported['id'] === (int) $actor['id'] before the privilege-ceiling check and rejects with a clear flash error. A mod can no longer file a report against themselves and then dismiss/warn/act on it to create a false audit trail.

Locking this thread.