Follow up of b2ee1770d4 and 10c2254d41, part of T74432.
Now the area and region naming conventions should be less confusing.
Mostly a careful batch rename but had to do few smaller fixes.
Also ran clang-format on affected files.
The 'random' unit tests and some examples from the new boolean code
triggered asserts and crashes. This fixes those.
There is a new flag in the input that optionally disables a pass
over input to snap segment edges to other segments.
A big rework of the code now uses exact predicates for orientation
and incircle. Also switched the main algorithm to use a faster
divide and conquer algorithm, which is possible with the exact
predicates.
Check was losing precision -- adjust by translating points
before calculating circumcircle.
Also, needed to check for flippability of edges before flipping.
Bugs were: (1) needed an epsilon test in CCW test in order to
handle new costraint edge that intersects an existing point
but only within epsilon; (2) the "valid bmesh" output mode
sometimes left a face that included outside frame point.
See Design task T68277, and patch D5423.
This commit includes edits by @ideasman42 to patch in
branch temp-D5423-update, plus responses to his comments.
