feat: Breadcrumbs on button clicks

[bitsandfoxes]

The idea is to auto-instrument all buttons present in scenes during build time (the OnProcessScene also gets called within the Editor).

[github-actions[bot]]

	Fails
:no_entry_sign:	Please consider adding a changelog entry for the next release.

	Messages
:book:	Do not forget to update Sentry-docs with your feature once the pull request gets approved.

Instructions and example for changelog

Please add an entry to CHANGELOG.md to the "Unreleased" section. Make sure the entry includes this PR's number.

Example:

## Unreleased

- Breadcrumbs on button clicks ([#864](https://github.com/getsentry/sentry-unity/pull/864))

If none of the above apply, you can opt out of this check by adding #skip-changelog to the PR description.

Generated by :no_entry_sign: dangerJS against 5cb679de8ab61b24bee79f0a790eb91d8e3365f9

[getsantry[bot]]

This issue has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you remove the label Waiting for: Community, I will leave it alone ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀