TextArea can't auto-size based on content

[rock3r]

When you have a BTF:

Box(
  Modifier.heightIn(min = minTextAreaHeight, max = maxTextAreaHeight),
  contentAlignment = Alignment.TopStart,
) {
  BasicTextField(state = myState, modifier = Modifier.fillMaxWidth())
}

It will size itself based on the number of text lines in the state, and the heightIn modifier. When empty, it matches the min; when there are too many lines to fit in the max it'll stop growing and start scrolling.

However, the same does not happen with TextArea:

Box(
  Modifier.heightIn(min = minTextAreaHeight, max = maxTextAreaHeight),
  contentAlignment = Alignment.TopStart,
) {
  TextArea(state = myState, modifier = Modifier.fillMaxWidth())
}

The TextArea will always stretch until max, regardless of its text contents.

[rock3r]

It may be worth simplifying how the TextArea scrollable layout is handled, by decoupling it from ScrollableContainer, and/or fix the ScrollableContainer implementation. The main issue is that doing a 2D scrollable container adds a lot of complexity and requires a number of compromises, and it's even unclear if 2D scrolling in Compose for Desktop is working at all anyway. We should likely deprecate/remove the 2D version and focus on one axis only until proper support at a higher level than draggable2D is available in Compose.