T14: penanda vote basi (last_vote dari rasio bobot/stake, filter ?stale=1, VEX_STALE_DAYS)

config.py

@@ -31,3 +31,6 @@ DASH_PORT = int(os.getenv('DASH_PORT', '5000'))
 
 # Dashboard: jumlah worker gunicorn (produksi)
 DASH_WORKERS = int(os.getenv('DASH_WORKERS', '2'))
+
+# Ambang batas vote "basi" (hari tanpa revote) untuk penanda staleness
+VEX_STALE_DAYS = int(os.getenv('VEX_STALE_DAYS', '28'))