* [TD]Cosmetic geometry and tools update
- all cosmetics to store geometry in same form
- all cosmetics to survive scaling and rotation
- extension functions to survive scaling and rotation
* [TD]overhaul leader point storage and editing
- add py routine makeLeader(points)
* [TD]add leader conversion utility
* [TD]Set Leader RotateWithView default to true
* [TD]fix intersection vertex position
* [TD]add CosmeticEdge::makeLineFromCanonicalPoints
* [TD]fix 2 Extension tools
- positioning in DrawCosmeticCircle
- mishandling of points in execLineParallelPerpendicular
* [TD]Remove duplicate constexpr
* [TD]fix 2x Cosmetic arc tools
* [TD]refactor LineFormat out of Cosmetic
* [TD]move cosmetic appearance settings to LineFormat
* [TD]remove 2 unused methods
* [TD]apply format to blue line & circle tools
* [TD]fix ballon arrowhead does not rotate with view
* [TD]fix CosmeticCircle3Points
* [TD]allow multiple cosmetic object deletions
* [TD]fix extend/shorten centerline
the PR fixes the following things:
- change the way centerlines between 2 lines are calculated. The current implementation leads to many bugs and even crashes (e.g. when the 2 selected lines are parallel ones of a square). There are different forum threads from the last 1.5 years.
The new endpoint line sorting is the one described here: https://forum.freecadweb.org/viewtopic.php?f=35&start=20&t=44255&sid=989a668890f954c13ef81e4a04ee6912#p501179
- as consequence the erroneous and misleading line end flipping can go and is removed (only used internally)
- when creating a new centerline, you see it immediately
- when creating a new or editing an existing centerline and press Cancel, the creation/editing is aborted
- fix crash when the 2 selected lines are bot horizontal and one tries to create a vertical centerline
- fix crash when changing the orientation of an existing centerline and the result would be invalid
- cleanup the code a bit
