v0.3.0 — anti-flood throttling, entity cache, 20 new tools, observability Major feature release. Backwards compatible — all existing endpoints unchanged, new functionality opt-in via env vars with safe defaults. Highlights: - Per-method token buckets + per-chat send/read intervals + adaptive backoff on FLOOD_WAIT. Defaults sized to stay well under Telegram's observed soft limits without manual tuning. - Persistent entity cache survives container restarts — repeated resolveUsername calls become free cache hits. - 20 new tools including bulk_resolve, reactions, pins, polls, channel admin, account_health, throttle_status. - /metrics Prometheus exposition, /ws/updates websocket, outbound webhook via TELETHON_POST_TO_URL. - TELETHON_READ_ONLY and TELETHON_DRY_RUN safety switches. - 44-test unit suite that runs without Telegram (`make test-unit`).