chore/breaking: simplify scalar types

[ra0x3]

Thanks for opening a PR with the Fuel Indexer project. Please review the Checklist below and ensure you've completed all of the necessary steps to make this PR review as painless as possible.

Checklist

• [ ] Ensure your top-level commit message is in line with our contributor guidelines.
• [ ] Please add proper labels.
• [ ] If there is an issue associated with this PR, please link the issue (right-hand sidebar)
• [ ] If there is not an issue associated with this PR, add this PR to the "Fuel Indexer" project (right-hand sidebar)
• [ ] Please allow Codeowners at least 24 hours to do a first-pass review.
• [ ] Please add thoroughly detailed testing steps below.
• [ ] Please keep your Changelog message short and sweet.

Description

• PR simplifies our usage of scalars
• We had a lot of scalars that we weren't really using
  • I think previously the idea was to "alias things in a friendly way", but aliasing turned out to just generate a lot of unnecessary scalars
  • After some time, I think it's better to have fewer scalars
  • This was first suggested by JC (which I agreed with)
• Also changes the name of some scalars to make them more idiomatic
  • E.g., Int8 to I64 to be more in line with GraphQL standards (obviously we're still using types that GQL doesn't implement)
• Obviously this is a pretty breaking change
  • I'll be sure to include a prominent section in the release changelog for this

Testing steps

• [ ] CI should pass
• [ ] QA run report is attached

Changelog

• chore/breaking: simplify scalar types

[ra0x3]

QA script results on this branch Rashads-Air.lan-2023-09-28.indexer-qa.txt