Change the behavior of transform and set-handle-type to operate on both
handles when the knot is selected.
This was an oversight in [0] which changed selection to select the knot
without the handles.
This makes curve bezier handles picking & transform match the Graph
Editor & grease pencil bezier curves.
This fixes issues transforming a bezier knot:
- Auto handles would be converted to "Aligned".
- Vector handles would be converted to "Free"
with the vector handles being left in-place.
Resolves#111840.
Details:
Selecting only the knot vertex was done because the tweak tool no longer
de-selects when picking an already selected vertex to allow tweak to be
used to transform the selection (instead of always de-selecting all
before tweaking). Without this change, dragging a single handle required
manually de-selecting the knot and the opposite handle (3 clicks to
select a handle before dragging). Selecting only the knot solves this
but means transform needs to support tweaking a vertex (& it's handles)
without it's handles selected.
See design #96544.
[0]: 618f39fca2
90864d3fb8