Remove the forces_endpoint_snap mechanism merged in #293:
CadCommand::forces_endpoint_snap, Snapper::snap_forced_corners /
forced_corner_modes, the PlotWindowCommand override, the on_tick +
click-commit wiring, and the associated tests. PLOTWINDOW now uses the
normal snapper like every other command.
Rationale: forcing Endpoint snap on regardless of the global OSNAP master
overrides an explicit user setting and is surprising — a plot window is a
coarse print region that usually wants a margin, not a corner lock, and
the forced set only caught Endpoint (not center/mid/intersection) so it
was a partial, opinionated helper. Parking it pending a design discussion
with the PR author; can be reinstated behind a clearer UX (e.g. respecting
OSNAP, or an opt-in modifier) if justified.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>