[refactor] reacharound placement feature

[lonefelidae16]

Refactor the feature of ReachAround placement. Shorter lines, more maintenability.

also resolve #211

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Checklists

Compatibility

• with Reacharound

Block placement

• Non-full block (updated)
  • Dirt Path
  • Soul Sand
  • Mud
  • Chests
  • Chain
  • Stonecutter
  • Grindstone
  • End Rod
  • Bed
  • Stairs, also on half position
  • Slabs, also on upside-down position
  • Fences
  • Walls
  • Cake
  • Amethyst Buds, Cluster
  • Sea Pickle
  • Flower Pot
  • Carpets
  • Trapdoors
  • Lectern
  • Enchanting Table

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Changes

• update ReachAroundPlacement.java

  • removed methods:
    • isNonFullBlock, use Entity#getSteppingPos instead
    • checkReachAroundAndExecute, due to injection method has changed
  • method access modifier has changed:
    • canReachAround: private -> public
  • in method canReachAround:
    • use Entity#isOnGround instead of checking the BlockState
    • use Entity#getSteppingPos instead of BlockPos#down to avoid collision error

• update MinecraftClientMixin.java

  • modify MinecraftClient.crosshairTarget instead of executing the unique method checkReachAroundAndExecute