[pigeon] Adds SwiftFunction annotation

[ailtonvivaz]

This PR adds a new annotation to Swift Generator to control the naming of a function like there is for ObjC (the annotation @ObjCSelector) as requested in https://github.com/flutter/flutter/issues/105932

Pre-launch Checklist

• [x] I read the Contributor Guide and followed the process outlined there for submitting PRs.
• [x] I read the Tree Hygiene wiki page, which explains my responsibilities.
• [x] I read and followed the relevant style guides and ran the auto-formatter. (Unlike the flutter/flutter repo, the flutter/packages repo does use dart format.)
• [x] I signed the CLA.
• [x] The title of the PR starts with the name of the package surrounded by square brackets, e.g. [shared_preferences]
• [x] I listed at least one issue that this PR fixes in the description above.
• [x] I updated pubspec.yaml with an appropriate new version according to the pub versioning philosophy, or this PR is exempt from version changes.
• [x] I updated CHANGELOG.md to add a description of the change, following repository CHANGELOG style.
• [x] I updated/added relevant documentation (doc comments with ///).
• [x] I added new tests to check the change I am making, or this PR is test-exempt.
• [x] All existing and new tests are passing.

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Validations Fail.

[stuartmorgan]

@ailtonvivaz Is this still something you're planning to update?

[flutter-dashboard[bot]]

This pull request is not mergeable in its current state, likely because of a merge conflict. Pre-submit CI jobs were not triggered. Pushing a new commit to this branch that resolves the issue will result in pre-submit jobs being scheduled.

[tarrinneal]

@ailtonvivaz I've updated this to the latest changes on the main branch.

Were you still planning to make these changes requested by @stuartmorgan? https://github.com/flutter/packages/pull/2304#discussion_r958876417

[ailtonvivaz]

@stuartmorgan @tarrinneal

I'm sorry, I will continue working on the feature, making the adjustments as pointed out

[tarrinneal]

@stuartmorgan @tarrinneal

I'm sorry, I will continue working on the feature, making the adjustments as pointed out

We're all busy, it's totally fine. If you end up not having time to work on it, let me know.

[tarrinneal]

It appears you've broken some swift code/tests.

Also, make sure to run the formatter cl tool with

dart pub global run flutter_plugin_tools format --packages pigeon

to clean up the generated files before uploading them.

[tarrinneal]

Sorry, I was wrong about the breaking change. I reverted it back to 6.0.4.

[tarrinneal]

I think if you can fix these last few nits, and merge with main again, we should be able to land this shortly :)

Thank you for the time and effort you put into this pr!