PlateToolManager keeps one active tool with the WinForms action rules
(Escape cancels, then returns to Select, then resumes the ended tool) and
status text. SelectTool selects by click, Ctrl+click and window
(contains/intersect), takes common-line groups together and picks
cut-offs by their strokes. PlateHitTester hit-tests the shared display
geometry; PlateSelection reads and sets by part index.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
