Match function and declaration names, picking names based on
consistency with related code & clarity.
Also changes for old conventions, missed in previous cleanups:
- name -> filepath
- tname -> newname
- maxlen -> maxncpy
This simplifies code using these functions because of RAII,
range based for loops, and the lack of output arguments.
Also pass object pointer array as a span in more cases.
Pull Request: https://projects.blender.org/blender/blender/pulls/117482