Allow continuous recording of voice messages + playback before sending voice messages

Is your feature request related to a problem? Please describe.

The mobile versions of Spreed (NextCloud Talk) lack two features compared to the web counterpart:

1. Automatic continuous recording of voice messages;
2. Ability to playback the recorded message before sending it to the recipient;

On the web version of spreed, it is possible to record voice messages by clicking the microphone icon. Once the recording starts, it is possible to complete the recording (via the green button with the white check mark) or to discard it (via the red button with the X). Then, the user can playback the recorded message before sending it to the recipient.

On both mobile (NextCloud Talk) versions (Android and iOS), it is also possible to record voice messages by tapping on the microphone icon, but you must do a long press and hold it for as long as you want the recording to last (you don't have to hold the left mouse button on the computer to allow continuous recording on the web version).

So if I record a 5 minute voice message, I must keep the finger glued to the phone screen for 5 minutes. This is inconsistent compared to the desktop version. It is frustrating when one is in the middle of the recording and accidentally lifts the finger.

Describe the solution you'd like
The mobile versions (NextCloud Talk) should replicate the same usage of the web version.

1. You start the recording by tapping on the microphone icon.
2. The red and the green button appears on screen.
3. The user presses the green button to complete the recording.
4. A preview of the message is shown on screen (same as the web version)
5. The user can playback the voice message before sending it to the recipient.
6. The user can send or dismiss the voice message that has been recorded.

Describe alternatives you've considered
One alternative would be for the lock icon to appear on screen, above the microphone button, so that the user could swipe up the finger and then lift it and the recording could still go on.

Additional context
This feature is present in other messaging apps like Whatsapp and Telegram and it is useful.

Mobile app tickets

• https://github.com/nextcloud/talk-ios/issues/886
• https://github.com/nextcloud/talk-android/issues/2790

Start by reviewing the linked mobile app tickets: talk-ios issue 886 and talk-android issue 2790. Compare their current scope with this request for tap-to-start recording, completion or dismissal controls, preview, playback, and sending; the work is done when both mobile versions provide that flow consistently.