[Dart/Flutter]: v9 Main Tasks

[vaind]

v9 Pre-work

• Reminder: check if anything else needs to be deprecated or removed

v9 Main Tasks

See sub issues below

[buenaflor]

If needed we can also currently push things to the v9 branch

[vaind]

If needed we can also currently push things to the v9 branch

some of these would just cause merge conflicts down the road so I'd suggest doing them later closer to the release.

[vaind]

In my recent work on the replay, I've come across the need to use Uint8List.address which is available since Dart SDK 3.5 - we should consider this as a target when bumping a major version because that would enable significant performance improvements (no need to copy screenshot data in dart when sending to native)

[buenaflor]

3.5.0 sounds reasonable, data also looks good to argue why we could bump it to that version

@denrase will start with the dart version bump on v9