Fix metadata reshaping when time dim is implicit and the split file dim array has time as a dimension

Finish metadata reshaping for retrieve = TRUE, including different combinations of merge_across_dims, merge_across_dims_narm, and split_multiselected_dims

Change function chunk_indices() to get_chunk_indices() because chunk_indices is an item in some functions

Start() can correctly merge files along the dimension that has different length each file, without additional NAs.