Unify inside & outside position alignment

[zsoltk]

Description

Related issue

• Replace offset values with alignment #564 created a separate class for PositionOutside, meaning we ended up with two classes that could affect alignment: One for inside the container, one for offsetting whole screen distances for scrolling.

Problems

• .align() can only be applied once in a Modifier change, only the first one having effect
• Following from this, we could have either outside alignment or inside alignment, but not both
• This blocks implementing a shared element transition from a list (outside alignment) to a detail screen (hero element changes alignment inside the screen)
• Adding outside alignment bias into Position isn't possible since it already maxed out 4D for its AnimationVector (2 for alignment bias, 2 for relative offset coordinates), a hard limit imposed by Compose.

Approach in this PR

• Extract out the relative offset to a standalone property: PositionOffset which only takes a DpOffset
• This frees up 2 dimensions in the AnimationVector that we can use for outside alignment instead
• Merge PositionInside and PositionOutside 2+2 alignment bias values into a single property PositionAlignment
• The new property can account for both inside and outside alignment in a single modifier correctly

Migration steps for client code

In any client code TargetUiState instances:

• Replace usages of PositionInside and PositionOutside with PositionAlignment
• Wherever an extra offset was also used next to alignments, also introduce a new field for PositionOffset and move the value there

Check list

• I have updated CHANGELOG.md if required.
• I have updated documentation if required.

[KovalevAndrey]

Suggested change

	val value = renderValueFlow.collectAsState()
	val boxScope = requireNotNull(LocalBoxScope.current)
	with(boxScope) {
	this@composed
	.align(value.value)
	val value = renderValueFlow.collectAsState()
	val boxScope by requireNotNull(LocalBoxScope.current)
	with(boxScope) {
	this@composed
	.align(value)