Expose the timeline item long press and swipe to reply as TalkBack actions

[hayaksi1]

Content

A timeline item carries two gesture-only actions: long press opens the message action list, and a horizontal swipe starts a reply. Neither is reachable with TalkBack enabled, so a screen reader user cannot reach the action list at all — this is what the issue reports.

Publish both as accessibility custom actions on the event row, reusing the existing "Message actions" and "Reply" strings so no new translations are needed. The reply action is only offered when the user is allowed to reply, matching the condition that enables the swipe.

The scope is deliberately limited to restoring actions that already exist for sighted users. The larger list discussed on the issue — react, edit, share, links, view profile — is a product decision about which actions deserve to be surfaced directly rather than through the action list, so it is left out.

Motivation and context

Part of #4600.

Tests

No new automated test: the module's timeline view tests assert on rendered content, and Robolectric does not run the accessibility delegate that turns customActions into TalkBack actions, so a test here would only re-assert the semantics property I just set.

Manual check: with TalkBack on, focus a message and open the local context menu — "Message actions" and "Reply" are listed, and each performs the same action as the gesture.

Tested devices

• Physical
• Emulator
• OS version(s):

Checklist

• I am aware of the etiquette.
• 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]

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