fix(handler): ensure lastChange is preserved and improve commit message handling

[karnirathorewolf]

This pull request addresses a bug in the image reference update logic and adds a corresponding test to ensure correct behavior. The most important changes are:

Bug Fix: Image Reference Update Logic

• Fixed an issue in the ImageRefUpdateFilter.Filter method where the lastChange could be overwritten by an empty Change from non-matching image references, ensuring that only meaningful changes are recorded.

Testing

• Added a new test, Test_lastChange_preserved, to verify that the lastChange is not overwritten by empty changes when multiple image references are processed and only one matches, preventing regressions of the fixed bug.This pull request addresses a bug in how image reference updates are processed and committed, ensuring that changes from multiple image refs are handled correctly and that commit messages accurately reflect all changes. It also introduces new and improved tests to verify this behavior.

Bug fix and processing improvements:

• Fixes fix: handle commit message format errors #69
• Fixed a bug in ImageRefUpdateFilter.Filter so that when evaluating a YAML node against multiple image refs, the Change from a matching ref is no longer overwritten by empty changes from non-matching refs. This ensures that only relevant changes are recorded and described.
• Refactored KoboldHandler in task/handler.go to process each image ref message independently, accumulating all changes and warnings, and generating separate commits for each message. The final push includes all accumulated changes, and commit messages now include all relevant change descriptions, even for the same repo.

Testing improvements:

• Added a regression test Test_lastChange_preserved to ensure that only the matching image ref's change is preserved and not overwritten by empty changes.
• Enhanced TestGetCommitMessage to verify that commit messages include all changes, even when multiple changes pertain to the same repo but have different descriptions. [1] [2]
• Added new tests TestKoboldHandler_separateCommitsPerMessage and TestKoboldHandler_multipleMessagesAccumulate to confirm that each message results in a separate commit and that all changes are accumulated and pushed together.

Test setup and imports:

• Updated test files to include necessary imports for new tests and functionality.
  This pull request addresses a bug in the image reference update logic and adds a targeted test to ensure correct behavior. The main focus is on preserving the correct change information when multiple image references are evaluated, preventing a valid change from being overwritten by an empty one.

Bug fix in image reference update logic:

• Ensured that the lastChange variable is only updated when a matching image reference has a non-empty description, preventing it from being overwritten by empty changes from non-matching refs in ImageRefUpdateFilter.Filter (krm/filter.go).

Testing improvements:

• Added Test_lastChange_preserved to verify that the correct Change is preserved when multiple image references are evaluated, and only one matches. This test ensures that the bug does not regress in the future (krm/filter_test.go).

[bluebrown]

this makes sense to me. Returning a boolean indicating match might be cleaner.
Similar to signature like https://pkg.go.dev/strings#Cut

[bluebrown]

I am confused about the changes here in the handler. This looks extremly dirty.
Initially thought the only change made was in filter.go.

On first glance this doesnt seem required or at the very least its filled
with redundant safety checks. I.e. checking empty string on a sql.NullString.

[bluebrown]

I think there might be already existing table tests. Or this should be a table test.
Comments smell alot like AI.

[bluebrown]

Generally speaking. I can see that this has been AI generated. I would like to discuss this change
and the reasons but this is likely not possible. Especially not if the requester doesnt fully understand
what the AI did generate.

All in all, it does likely show the actual root cause. It does likely fix it in non idiomatic ways, containing
redundancy and other AI artifacts.

[bluebrown]

Oh here it says:

Refactored KoboldHandler in task/handler.go to process each image ref message independently, accumulating all changes and warnings, and generating separate commits for each message. The final push includes all accumulated changes, and commit messages now include all relevant change descriptions, even for the same repo.

This is completely wrong. We do not want to make multiple commits. At least there isnt a good reason to.
All changes go on the same branch in the same commit, with a bullet point lists of changed images.

Further, if you were to make multiple commits, then you should remove any bullet point list rendering,
as the list can never have more than one item. So the current PR is mixing concepts.

I think multiple commits is not wanted or out of scope of this PR. Can open extra issue, if this is desired.

[bluebrown]

resolve #66