Remove metrics

[adinauer]

📜 Description

Remove metrics API and internal classes.

Metrics will return in the future but we don't know in what form exactly.

💡 Motivation and Context

Closes #3732

💚 How did you test it?

📝 Checklist

• I reviewed the submitted code.
• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

🔮 Next steps

[github-actions]

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

	Messages
📖	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

- Remove metrics ([#3774](https://github.com/getsentry/sentry-java/pull/3774))

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

Generated by 🚫 dangerJS against 4b083a0

[markushi]

🫡 nice one! I did a grep on top and couldn't find any remaining leftovers.

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	411.09 ms	496.54 ms	85.45 ms
Size	1.70 MiB	2.35 MiB	665.37 KiB

Previous results on branch: feat/remove-metrics

Startup times

Revision	Plain	With Sentry	Diff
c6c2c24	442.86 ms	459.00 ms	16.14 ms

App size

Revision	Plain	With Sentry	Diff
c6c2c24	1.70 MiB	2.35 MiB	665.37 KiB

[sysmat]

are any alternatives for Sentry.metrics()?

[adinauer]

@sysmat we're still figuring out how it'll work in the future, can't say when we have something to share