Path: Fixes #6849 - Properly cancel new Lead In/Out dressup [Hold]

[Russ4262]

Make modifications to viewprovider and taskpanel classes to properly handle cancellation of new lead in/out dressup when Cancel button is pressed.

Forum discussion at Bug: LeadInOut dressup created on Cancel.

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[berndhahnebach]

for feature branch PR_7130. Pipeline 579735902 was triggered at e38945c. All CI branches and pipelines.

[sliptonic]

I don't have a problem merging this as it solves the problem and works as described.
Without digging farther into it, I'm curious why the solution is needed though.
Isn't the dressup being created within a transaction? Shouldn't aborting that transaction occur if the user hits cancel?
It seems odd that we need to initiate and complete a transaction to remove the dressup when it shouldn't have been created at all.

[Russ4262]

My thought was the same, that aborting the transaction should work. Unfortunately, there appears to be more at play. As for the solution in this PR, it is modeled after PathOpGui code usage.

There is another solution that involves a refactor. We can back burner this PR. I can convert this PR to draft.
Offending line is

FreeCAD/src/Mod/Path/PathScripts/PathDressupLeadInOut.py

Line 772 in e0a7332

FreeCAD.ActiveDocument.commitTransaction()

. But this line is not the only offending code for proper Cancel button functionality.