[Story] Voice message analytics

[jonnyandrew]

Description

Add analytics for voice messages.

Acceptance criteria

• When user taps the send button the following event is tracked to Posthog:
  • Event: Composer
  • Property: isVoiceMessage
• Only send if user has given consent for analytics

Size estimate

None

Dependencies

• 2084

• 2104

Preconditions

Sign-off

Android

• [ ] QA sign-off on completion
• [ ] Product sign-off on completion

iOS

• [ ] QA sign-off on completion
• [ ] Product sign-off on completion

Out of scope

Open questions

Subtasks

### Android
- [x] Event is tracked on tapping send button https://github.com/vector-im/element-x-android/pull/1706

### iOS
- [x] Event is tracked on tapping send button
- [ ] https://github.com/vector-im/element-x-ios/pull/2019

### Other
- [ ] https://github.com/matrix-org/matrix-analytics-events/pull/86

[jonnyandrew]

Blocked waiting for https://github.com/matrix-org/matrix-analytics-events/pull/86