* wdclient, dailyrun: add equal jitter to retry backoff
Prevents thundering-herd retries when many clients recover from a
transient failure at the same instant (e.g., filer restart, network
partition healing).
Uses equal jitter: wait in [d/2, d) instead of deterministic d.
This bounds the maximum wait while still desynchronizing clients.
Files:
- weed/wdclient/filer_client.go (LookupVolumeIds retry loop)
- weed/s3api/s3lifecycle/dailyrun/dispatch.go (dispatchWithRetry)
Tests added for bounds, zero/negative inputs, and distribution sanity.
Closes#9735
* wdclient: honor ctx cancellation during LookupVolumeIds backoff
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Co-authored-by: Mohamed Chorfa <mohamed.chorfa@thalesgroup.com>
Co-authored-by: Chris Lu <chris.lu@gmail.com>