fix: implement topBitSetTerminatedArray, fix nbt TAG_End, fix entity_equipment

- Implement topBitSetTerminatedArray decoder/encoder with MSB continuation
- Fix nbt.Tag.Decode to handle TAG_End at root level (fixes 1.8 slot NBT)
- Remove 228 now-passing decode failure tests, keep 10 still failing
- EntityEquipment now works correctly across all versions

mc/nbt/nbt.go

@@ -68,6 +68,9 @@ func (s *Tag) Decode(r io.Reader) (err error) {
 	if err != nil {
 		return
 	}
+	if id == End {
+		return
+	}
 	var name any
 	name, err = readPayload(String, r)
 	if err != nil {