scaling up the check_block_function

[pattonw]

The block done checking is currently a bit rough with 2 main problems that I regularly encounter:

1. it can take a while
2. there's no progress bar

Regardless of how fast your check block function is, daisy still requires every block be check individually, so as we get into many millions, or billions of blocks, the check function becomes a nuisance.

I think we should change the check block function signature from:
check_block(block: Block) -> bool
to
check_block(block: Block) -> bool | Roi
where if a Roi is returned, we mark all blocks contained in that roi as done. This way we could save the blocks done in a scale pyramid, and when we check a block, just travel up the pyramid to mark the maximum number of blocks done all at once. This should make the check time scale with the log of the number of blocks, instead of linearly which would be significantly nicer to use.