feat: add operator-only notes field per request

models.py

@@ -44,7 +44,8 @@ CREATE TABLE IF NOT EXISTS requests (
     admin_alert_email TEXT,  -- reserved for future operator alerts; currently unused
     player_token TEXT NOT NULL UNIQUE,
     revision_count INTEGER DEFAULT 0,
-    revision_note TEXT
+    revision_note TEXT,
+    operator_notes TEXT
 );
 
 CREATE INDEX IF NOT EXISTS idx_requests_status ON requests(status);