Physical Falling Trees

• Added a new mechanic — falling tree under gravity;
• Added support for stained leaves depending on vanilla biomes;
• Optimized the transformation of a tree into a falling tree;
• Fixed bugs with the initial falling tree block.

For devs: there are 5 stained leaves in total (oak, jungle, acacia, dark_oak, mangrove leaves), by default they do not support other models from vanilla blockstates, you need to go to the physical_falling_trees/items/leaves.json path in the file and change the paths to the models depending on your goals.