fix(ios)!: use AVAudioSessionCategory.playAndRecord as default

[wujek-srujek]

Description

Now if ducking is requested, iOS doesn't crash. Also, the default instance of AudioContextIOS in Dart corresponds to the one in Swift, making the feature consistent.

Checklist

• The title of my PR starts with a Conventional Commit prefix (fix:, feat:, docs:, chore: etc).
• I have read the Contributor Guide and followed the process outlined for submitting PRs.
• I have updated/added tests for ALL new/updated/fixed functionality.
• I have updated/added relevant documentation and added dartdoc comments with ///, where necessary.
• I have updated/added relevant examples in example.

Breaking Change

• Yes, this is a breaking change.
• No, this is not a breaking change.

Yes, it is a breaking change because it changes the default value for the audio category on iOS if the user doesn't specify it explicitly when creating a new AudioContextIOS.

Migration instructions

If the user wants the category to be playback, they need to set it explicitly.

Before:

final context = AudioContextIOS();

After:

final context = AudioContextIOS(
  category: AVAudioSessionCategory.playback,
);

Related Issues

Closes #1491

[Gustl22]

Thanks. If breaking I would want to wait for the next major release and also ensure, if we could make playback the default.

Until then this config should fulfill your needs:

AudioContextIOS(
    category: AVAudioSessionCategory.playAndRecord,
    options: [
        AVAudioSessionOptions.mixWithOthers,
        AVAudioSessionOptions.duckOthers,
    ],
)

[Gustl22]

I think it's fine to use the playAndRecord as default, makes the library a bit more expectable. Can't test it though ;D

[Gustl22]

@wujek-srujek can you validate if you can play the sound through the headphones, if using playAndRecord as default?
See: #1486 (comment)
Otherwise it would be a good reason to use playback as not being able to play through a headset is not expected to happen.

[wujek-srujek]

Unfortunately I won't be able to do it for about 3 more weeks due to vacation and very limited connectivity (and no computer), but will get to it afterwards.

Discussion in #1486 shows that this is probably not the right default value.

[Gustl22]

As stated here (#1545 (comment)) earpeace only is equal to playAndRecord. So switching to playback as default would allow BT headphones, while also let the sound coming from speakers by default.

[Gustl22]

This should now be solved in #1563. We would be glad if you could verify. Feel free to reopen, if the issue isn't solved.