Round-robin DNS management for MTProto proxy failover:
on  — set all three A records (91.232.225.3, 95.47.184.52, 217.12.37.55)
off — keep only primary IP
Uses nsupdate -l (local) for running on ns1.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>