resolved_allowlist_user_ids() returned every numeric ID in the adapter's
connect-time _allowed_user_ids, and the gateway authz layer unions that set
into the reloaded DISCORD_ALLOWED_USERS. So an ID removed from the allowlist
after connect (hermes pairing revoke from the CLI or dashboard, or a hand
edit) kept authorizing until the gateway restarted. #130920's in-place purge
only reaches adapters in the same process, and those commands run outside it.
Track the IDs _resolve_allowed_usernames actually resolved from username
entries and return only those: they are what the per-turn .env reload loses
(a0a63a1bc2); numeric entries are already read live from the env.
(cherry picked from commit 90451505545745dbb27ecad28f2c431ad5afd301)
462389ea5e