Adding compact check functionality to GenericByteViewArray

[ClSlaid]

This part contains compact check functionality for GenericByteViewArray.

Which issue does this PR close?

Rationale for this change

Part of #5707.

What changes are included in this PR?

• Enables GenericByteViewArray to check if its representation is compact.

Are there any user-facing changes?

None.

[alamb]

Thanks for this PR @ClSlaid

Would it be possible please to make a PR with ::gc() as described on #5720? first?

I think the logic to check for compacted is a nice (but new) additional API

This PR doesn't add any new APIs to ByteViewArray -- if we want to consider this code, perhaps we could add one like `GenericByteViewArray::is_compacted()?

But again i consider this a separate task

[ClSlaid]

Would it be possible please to make a PR with ::gc() as described on #5720? first?

I'd implement this first, instead of simultaneously or later.

So that I will not bother resolving git conflict 🪢, or have to implement a wasteful full-copying GC algorithm first. :P

This PR doesn't add any new APIs to ByteViewArray -- if we want to consider this code, perhaps we could add one like `GenericByteViewArray::is_compacted()?

As you wish, a new is_compacted :: &Self -> bool method is added.

But again i consider this a separate task

Exactly.

[ClSlaid]

@alamb Would you kindly retrigger the CI? I don't see anything wrong with my code.
Merge this PR and then we can push forward implementing GC.

[alamb]

@alamb Would you kindly retrigger the CI? I don't see anything wrong with my code. Merge this PR and then we can push forward implementing GC.

I believe the CI errors are due to issues that are subsequently fixed (@tustvold fixed #5719 this morning)

Thus if you merge up from the master branch you should be able to get a clean CI run

[alamb]

I am very excited to see GenericByteViewArray::gc 🙏

I still don't fully understand the need for the compact check API in this PR. Perhaps we can make a PR for gc first and then revisit this?

[ClSlaid]

will rewrite after GC merged