Update to 1.21.5-1.21.10

Improve snowing algorithm, add compat with FabricSeasons

• Improve snowing algorithm slightly
  • Add support for powdered snow in snowing algorithm calculations
  • Add support for blocks which don't have full faces on all sides
• Fix issue where snow layers would not stack past 8
• Fix grass disappearing with more than 1 snow layer
• Add compat for FabricSeasons

Update to 1.21.4 (should work on 1.21.1-1.21.4, however only 1.21.4 has been tested)

Reverts changes in previous release due to it only working when both client & server have the mod

Bring snow back to normal after snowing.