Follow-up to #28455. The respawn guard's blocker_auth rule (last error
matched a quota/auth/429 pattern) was auto-blocking the task on first
occurrence. That's too aggressive: transient rate limits typically
clear in seconds to minutes, but the auto-block puts the task in
'blocked' status which requires manual unblock.
Now treats blocker_auth the same as recent_success and active_pr:
defer the spawn this tick, leave the task in 'ready', let the next
tick try again. If the auth error genuinely persists, the existing
consecutive_failures counter trips the auto-block circuit breaker
after failure_limit failures via the normal path — so a persistent
401/403/quota-exhausted still ends up blocked, just not on first hit.
Also documents the respawn_guarded event in kanban.md's events table
with the three guard reasons.
Updated test_dispatch_respawn_guard_auto_blocks_auth_error → renamed
to test_dispatch_respawn_guard_defers_auth_error_without_auto_block;
asserts task stays in 'ready' and the guard reason is recorded.
7bcdced6c1