Strokes: Cannot create I strip when edges are connected and vert count is off

[jlampel]

If two edges are part of the same connected mesh island, then it is impossible to create an I strip between them unless they are the same number of verts away from the bridge that connects them.

For example, given this scenario:

You can create an I strip to the matching vert on the other side:

But if you try to draw to any other vert you will get a bad result:

However, if you break the two sides apart, the strip to that same vert will work fine:

This is an issue because the connection could be way on the other side of the mesh:

When this happens, no redo panel appears and there is no strip type reported. Instead, we get the following error in the console:

RFOperator_Stroke_Insert.execute: Caught Exception bpy_struct: item.attr = val: RETOPOFLOW_OT_strokes_insert.cut_count expected an int type, not NoneType
____________________________________________________________________________________________________
Exception Info
- Time: 2025-01-15 15:45:02.602676
- Count: 113
- Hash: cfc6b04d6e0ce6f1c8351ca228d6ab9e
- Info:
  - EXCEPTION (<class 'TypeError'>): bpy_struct: item.attr = val: RETOPOFLOW_OT_strokes_insert.cut_count expected an int type, not NoneType
  -     /Applications/Blender.app/Contents/Resources/4.3/scripts/modules/bpy_types.py
  - 000 0946:__setattr__() return setattr(properties, attr, value)
  -     /Users/jonathanlampel/Library/Application Support/Blender/4.3/scripts/addons/retopoflow/retopoflow/rftool_strokes/strokes.py
  - 001 0217:execute() self.cut_count = logic.cut_count

[jlampel]

Actually I also just noticed that it breaks in the following case where the verts do match up. I can draw from the top selected vert to the other side:

But not from the middle or bottom vert: