This rename the `Cutter` tool's name, code and icon to `Trim`.
The legacy Grease Pencil code is unchanged.
This was discussed in the 2024-07-30 Grease Pencil Module Meeting.
Reasons for the change:
- Match the `Trim Stroke Ends` setting on brushes.
- Match the `stroke_trim` operator.
- Name is more clear and more commonly used.
- Frees the name for a future boolean cutting tool.
Pull Request: https://projects.blender.org/blender/blender/pulls/126452
3c67ae7785