timestamp should be replaced with version in service workers #4196
Description
Describe the problem
#3412 added a version export to $app/env, which defaults to the timestamp at the time of builld. The $service-worker module doesn't expose it — it instead exposes a different timestamp.
Describe the proposed solution
Add version to $service-worker, and replace timestamp with an object that will throw a noisy error if you try to stringify it (which will cover the common case where it's used as a cache key).
Alternatives considered
No response
Importance
nice to have
Additional Information
No response