compat: Chipped & Eternal Starlight

TODO: Frosted Leaves and Northland Leaves need new snowy models with top and bottom textures. Perhaps I could change the default model to have bottom and top texture variables that by default take on the regular side texture.

assets/chipped/models/block/frosted_birch_leaves_top2.json

@@ -0,0 +1,6 @@
+{
+    "parent": "betterleaves:block/leaves2",
+    "textures": {
+        "all": "chipped:block/birch_leaves/frosted_birch_leaves_top"
+    }
+}