Unhardcode enchantment checks in tool drop handling

[screret]

What

The primary purpose of this PR is to unhardcode the enchantment checks in ToolEventHandler.onHarvestDrops and BlockMixin, as data packs can remove enchantments, which would make GTM crash.

I also:

• fixed the hammer & large miner drop conversion logic only ever checking the first recipe it came across and failing entirely if it's invalid (instead of checking all discovered recipes).
  • I don't believe this has been an issue so far, but it's better to fix now than to leave unfixed, right?
• cached the loot functions after they're created and made the hammer/large miner drops be deterministic based on the world seed (as they would be if the loot wasn't queried separately).
• elected to remove the SUPPLIER_ prefix from ToolHelper.POWER_UNIT_LV & co.
  • I'll add a copy of the fields with the old names and a deprecation warning if requested.
• removed any duplicated @NotNull/@Nullable annotations I came across.
• removed copies of vanilla break speed code in IGTTool.
• cleaned up a lot of the related code by using guard clauses instead of nested if statements.
• removed the two uses of the terminally deprecated bus property in @EventBusSubscriber.

Implementation Details

For all the applicable cases, I used the same utility function vanilla uses for silk touch: EnchantmentHelper.hasTag.
A tag for enchants that block hammer drop conversion was added for that. Currently, it only contains silk touch.

Outcome

• No more hardcoded enchantment checks
• Cleaner tool handling code
• Less warnings

Potential Compatibility Issues

Only compatibility issue is the rename of ToolHelper.POWER_UNIT_LV, _MV, etc., but that can be resolved easily enough.

[Reabstraction]

This PR touches many parts of the codebase and implements multiple separate changes. To make sure code is review-able, please extract individual changes out to either separate commits on this branch that are individually review-able, or separate PRs.