Skip indexing inscriptions when below first inscription

[andrewtoth]

After #1759 we skip indexing transactions when below the first inscription height, and fetch missing inputs afterwards. However, we still try and index inscriptions below the first inscription block during --index-sats.

This PR skips transactions below the first inscription block for --index-sats as well. With this method combined with #1812 I was able to sync --index-sats in 23 hours 42 minutes.

[jorge-j1m]

Probaly unrelated, but I've noticed that block committing takes a big chunk of the time needed to build an index, I don't know enough Rust to fiddle with that myself, but I feel like being able to manipulate the "checkpoints" (i.e. specifying how many blocks to allow between index commits) from the settings would be a good improvement, for me and most of use cases I know this is just a process in a server, fairly stable, so it's not super crazy to increase that threshold. I also don't know how easy/complicated a change it is, but being able to allocate more memory to the ord process should help as well. I can't help with the development, but if you make a PR I'm happy to test and report results @andrewtoth!

[andrewtoth]

@jorge-j1m I agree. There's a relevant issue https://github.com/casey/ord/issues/1630 if you want to share your thoughts there.