Add attachments support for user feedback

[tustanivsky]

This PR adds the ability to attach files and binary data to feedback submissions allowing users to include screenshots, logs or other contextual information alongside their messages.

Depends on:

• feat: Add attachment support to user feedback sentry-native#1414 (Windows/Linux)

At the moment Sentry Cocoa SDK limits attachments to a single file which is expected to be a screenshot.

Example feedback with two image attachments.

Closes #927

[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

### Features

- Add attachments support for user feedback ([#1121](https://github.com/getsentry/sentry-unreal/pull/1121))

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

Generated by 🚫 dangerJS against d602645