[prathshenoy]

Summary

What:

• Save one issue cursor and the planned change a worker must finish at that position.

Why:

• Save exactly which issue change must finish before moving on to newer work. A worker can stop after updating an issue but before writing its history, so a scan position alone is not enough to resume safely. Saving the intended change at that position lets another worker finish the same work.
• Preserve the issue version that the change was originally allowed to update. A retry must not read a newer version and use it to force an old change through. Only one planned change is needed at a time, so recovery does not require saving an entire batch.

Test Plan

• Add unit tests.
• Verify planned changes, cursor retention, and guarded updates against MySQL.

Revert Plan

• Revert dependent controllers first, then this PR. No runtime consumer is enabled; the added columns can remain unused.

Issue Links

• CODEM-607

Stack

1. feat(stovepipe): Retain versioned issue state #942
2. feat(stovepipe): Save planned issue changes #943
3. feat(stovepipe): Apply planned issue changes #932
4. feat(stovepipe): Track issues in bounded passes #940
5. feat(stovepipe): Publish issue-tracking updates #939