feat: apidiff-go release prerequisites

[erikburt]

This adds a few features to apidiff-go that will be needed for the automated release workflow (more context in #1432).

1. Based on the API differences, it will recommend a major, minor, patch version bump.
2. Copy the step summary file to a defined location, and output the path, this will be used as baseline release notes.

Changes

• Adds support for the above features
• Adds the ref and resolvedRef (if different) to the summary output
  • This will be nice when we're diffing between main and vX.Y.Z, we'll have historical SHAs in the summary.
• Cleans up unused stuff
  • A previous PR was going to add a lot of tag/versioning logic to this action, but I think thats a bad idea. So cleaned that up, and it's mostly replaced by feat: get-latest-tag #1432.
• Add support for workflow dispatch events, as before they would've errored immediately.
• Other small changes relating to the above

Testing

Unit tests are passing, testing locally produced good results.

Relates to

#1432

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DX-2323