## Summary
After a deployment promotion or rollback, newly triggered runs could
keep dispatching onto the previously deployed version for up to 30
seconds. Runs now resolve the current version fresh on every dequeue, so
a promotion or rollback takes effect immediately.
## Fix
The dequeue path resolved the worker version through a 30s in-process
cache that nothing invalidated on promotion, and it loaded the worker's
entire task and queue set only to keep the single row matching the run.
Both go away: the resolve now fetches just the matched task and queue by
unique index and reads them fresh, so there is no cache left to serve a
stale version.
```
- cache.get(env:current) # 30s TTL, never invalidated -> stale
- worker + ALL tasks + ALL queues
+ worker + one task WHERE slug=... + one queue WHERE id/name=... # fresh
```
A kill-switch env var (`RUN_OPS_WORKER_VERSION_FRESH_READ_ENABLED`,
default on) falls back to the old cached path without a code deploy.
Verified end-to-end on an isolated stack: a run triggered after a
mid-stream promotion now dequeues onto the new version, with the
previous stale behavior reproduced first.
Eric Allam
dc8f90e66e