Motschen's Better Leaves

Added compatibility for:

• Chipped
• Eternal Starlight
• BetterEnd (Cave Bush Leaves & Lucernia Leaves)
• Enderscape

Improved model variety

Allow leaves to have different top and bottom textures

Build-Process:

• Refactored the Python script into multiple files, improving code readability and maintainability
• Use the -d <zip-url|modrinth-slug> argument to download resourcepack zips or automatically grab the latest Modrinth release of a pack