In the merge_by_distance code, `vert_dest_map` is modified to become a vertex group map. But this is not clear from the code. Also use the `_map` suffix on `vert_final` and `edge_final`. And remove some unnecessary variables.
In the merge_by_distance code, `vert_dest_map` is modified to become a vertex group map. But this is not clear from the code. Also use the `_map` suffix on `vert_final` and `edge_final`. And remove some unnecessary variables.