Instead of 'extrude along path,' this would have the following benefits:
- path already created (eg. roof or slab)
- could easily select all connected edges along the same horizontal plane (eg. 'select all connected edges' making gutters for roof or footings for slab)
- option to constrain the extrude to those 3d edges (so it moves / lengthens with the 3d edge if the 3d edge is moved / lengthened)
- 'z' height already set
- extrude profile direction already set (ie. if symbol is used for profile, software could easily recognise which side of the 3d edge is 'outside')
