release-25.4: crosscluster/physical: fix ingest retry progress bug

[msbutler]

crosscluster/physical: fix ingest retry progress bug

This patch fixes two bugs in ingestWithRetries.

1. the resumer's job never has its in memory progress updated within a
   single resume, as the frontier processor writes progress updates
   directly to the db via job id.
2. previousPersistedSpans is never updated, which, in combination with
   the above, means, unless the job is resumed more than once, the
   branch to reset the retrier is never taken, as they are both always
   zero-values.

The fix is to refresh the resumer's job and update the previous value
each loop iteration.

Fixes: #167384

Release note: None

Co-Authored-By: roachdev-claude roachdev-claude-bot@cockroachlabs.com

Release Justification: low risk bug fix

[trunk-io]

😎 Merged successfully - details.

[cockroach-teamcity]

This change is 

[blathers-crl]

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