Fix mining tier check for Break Block, add hex_unbreakable tag

[Robotgiggle]

Implements a much simpler method for checking whether a given block is breakable by a given tier, and moves the function itself out of the xplat system and into HexUtils. Also, adds an empty tag json for hex_unbreakable, which was referenced in the previous tier checking system but not actually implemented.

[IridescentVoid]

Looks good to me. Checks performed:

• Code looks logically sound.
• Compiles and runs fine.
• Break Block attempted on:
  • Bedrock - failure (silent) as expected
  • Sandstone - success as expected
  • With the following tag change:
    • add(tag(HexTags.Blocks.HEX_UNBREAKABLE), HexBlocks.EDIFIED_PLANKS); (placed in HexBlockTagProvider.addTags and ran datagen)
    • Edified Planks - failure (silent) as expected
  • With the following tag change:
    • add(tag(BlockTags.INCORRECT_FOR_DIAMOND_TOOL), HexBlocks.EDIFIED_PLANKS);
    • Edified Planks - failure (silent) as expected
    • Sandstone - success as expected