v0.4.1

gerber-toolkit 0.4.1

Version 0.4.1 corrects mechanical-profile projection so pen-separated artwork
on an ambiguous mechanical layer is not inferred to be a destructive physical
cutout. Board discovery still accepts fragmented profile strokes, while
cutouts now require the stronger source semantics described below.

Mechanical-profile cutouts

• Unordered, reversible endpoint chaining remains available for discovering
  outer board profiles, including fragmented and disjoint outlines.
• A nested dark contour becomes an inferred cutout only when it is a Gerber
  region, its directed segments form a source-order-continuous closed path, or
  the layer has authoritative X2 FileFunction=Profile metadata.
• Clear-polarity closed geometry remains explicitly subtractive.
• Drawing frames assembled from pen-separated strokes remain non-destructive,
  while legitimate continuous, region-based, clear-polarity, and explicit X2
  profile cutouts retain their existing behavior.

API and compatibility

• No class, method, parameter, package subpath, parser input, or project input
  is added, removed, or renamed.
• Canonical document envelopes and the outline projector's return shape are
  unchanged. The correction only suppresses pcb_cutout rows that lack
  sufficient source semantics.
• Native retained geometry and shared renderer and scene-service inputs retain
  their existing shapes.

Performance normalization

• Profile chaining stops as soon as quantized endpoints prove that a path is
  closed, avoiding repeated full-path normalization during path growth.
• Line and sampled-arc points are normalized once when they enter outline
  projection, so source-continuity checks reuse the same finite point data.
• These changes preserve the corrected geometry semantics without adding an
  example-specific filter or downstream application workaround.

Verification

• Synthetic regressions cover pen-separated mechanical frames, legitimate
  source-continuous cutouts, closed contours followed by shared-vertex strokes,
  and quantized-degenerate sampled arcs alongside the existing profile suite.
• A provided fabrication archive was validated locally without being committed:
  canonical and native scene construction each exposed four physical cutouts,
  and neither exposed the spurious large rectangular cutout.
• Release gates are npm test, npm run check:format, and an inspected
  npm publish --dry-run using an isolated cache under /private/tmp.