Add bin project planning workflow

Merge pull request #38 from noobydp/gpu-birefnet-general

Add GPU-backed BiRefNet General tracer

Add per-object depth control

Each PlacedTool and FingerHole gains an optional depth_override that
takes precedence over the bin's global cutout_depth. Resolution is
fh.depth_override → polygon.depth_override → global, clamped to
[5, max_depth]. Chamfer is now clamped per-feature against its own
pocket depth so deep cutouts get a full chamfer and shallow ones
don't punch through the floor.

UI: select a placed tool to set the outline depth, or click an
individual finger hole to set the hole's depth. Empty input inherits;
× resets. CutoutOverlay was already interactive in the tool editor
and is now reused in the bin editor.

Closes #N (replace if you have an issue number)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

updates

Signed-off-by: Jason Madigan <jason@jasonmadigan.com>