Read all messages feature

[hghgrtut]

Content

Add functionality to read all messages in all rooms by one tap. Element X already has this functionality on iOs (https://github.com/element-hq/element-x-ios/pull/5582/changes)

Motivation and context

element-hq/element-meta#2682

Can be useful for example if you work at support and need to clear focus before your next work day.

Already added to iOs element-hq/element-x-ios#5582

Screenshots / GIFs

Tests

• go to home screen when you have unread messages
• go to developer settings
• click "Mark all rooms as read"
• confirm
• wait some time
• click read all button in toolbar (may be replaced with other action after review)
• messages are read

Tested devices

• Physical
• Emulator
• OS version(s): Android 15, Android 8.1, Android 7.0

Checklist

• This PR was made with the help of AI:
  • Yes. In this case, please request a review by Copilot.
  • No.
• Changes have been tested on an Android device or Android emulator with API 24
• UI change has been tested on both light and dark themes
• Accessibility has been taken into account. See https://github.com/element-hq/element-x-android/blob/develop/CONTRIBUTING.md#accessibility
• Pull request is based on the develop branch
• Pull request title will be used in the release note, it clearly defines what will change for the user
• Pull request includes screenshots or videos if containing UI changes
• You've made a self review of your PR

[github-actions]

Thank you for your contribution! Here are a few things to check in the PR to ensure it's reviewed as quickly as possible:

• If your pull request adds a feature or modifies the UI, this should have an equivalent pull request in the Element X iOS repo unless it only affects an Android-only behaviour or is behind a disabled feature flag, since we need parity in both clients to consider a feature done. It will also need to be approved by our product and design teams before being merged, so it's usually a good idea to discuss the changes in a Github issue first and then start working on them once the approach has been validated.
• Your branch should be based on origin/develop, at least when it was created.
• The title of the PR will be used for release notes, so it needs to describe the change visible to the user.
• The test pass locally running ./gradlew test.
• The code quality check suite pass locally running ./gradlew runQualityChecks.
• If you modified anything related to the UI, including previews, you'll have to run the Record screenshots GH action in your forked repo: that will generate compatible new screenshots. However, given Github Actions limitations, it will prevent the CI from running temporarily, until you upload a new commit after that one. To do so, just pull the latest changes and push an empty commit.

[bon3o]

I guess we need @element-hq/design assistance to finish our work on this PR.