TaskEntity.Number is a global, monotonically increasing, never-reused
integer (displayed as #123), allocated from AppSettingsEntity.NextTaskNumber
via a single UPDATE...RETURNING statement rather than MAX(number)+1, which
would reissue a deleted task's number. Both insert paths (TaskRepository.
AddAsync and CreateChildAsync) route through the new TaskNumberAllocator,
with a bounded retry on a unique-index collision. One migration adds the
columns, backfills existing rows in creation order, and creates the unique
index afterwards. Data-layer only; MCP/UI wiring is later slices.
The usage monitor polled the undocumented OAuth usage endpoint every 60s and
earned 429s. It now polls every 5 min while any task is Running and every
15 min while idle (usage_poll_interval_active_seconds / _idle_seconds, both
clamped to >= 60; the old single usage_poll_interval_seconds key is gone).
A 429 comes back as UsageRateLimitedException carrying Retry-After and adds
exponential backoff on top, capped at 30 min and never shorter than the normal
cadence; the strike count resets on the first success. The schedule arithmetic
is the pure static UsagePollSchedule.NextDelay.
Since the idle cadence is slow on purpose, WorkerHub.RefreshUsage drives
UsageMonitorService.RefreshNowAsync behind a Refresh now button in the Usage
Monitor modal: an out-of-band poll that pushes the loop's next-due time out so
no double poll follows, with a 10s cooldown so click-spam can't earn a 429.
Staleness now measures against the slower (idle) interval so an idle worker
isn't flagged stale just for not polling.
mika kuns