gerber-toolkit 0.3.0

gerber-toolkit 0.3.0

This coordinated minor release consumes the CircuitJSON Toolkit 1.2 canonical
PCB contract and hardens performance verification across development and CI
hardware.

API and compatibility

• The circuitjson-toolkit runtime baseline is now ^1.2.0, so Gerber
  documents interoperate directly with the same validated PCB text, rotated
  drilled-pad geometry, and primitive metadata accepted by the other source
  toolkits and the 3D viewer.
• Existing Gerber root exports, package subpaths, parser parameters, document
  envelopes, and extension APIs are unchanged from 0.2.0.
• All CircuitJSON 1.2 additions are additive; no Gerber feature is removed.

Release performance

• Comparable benchmark thresholds now account for the executing hardware while
  retaining the established absolute and relative regression requirements.
• Different environments continue to enforce deterministic result, clone,
  fixture, structural, metadata, warmup, sample, median, and retained-heap
  contracts without comparing non-equivalent wall-clock timings.
• The release checks exercise the comparable timing threshold explicitly,
  preventing a fast reference machine from producing false failures on
  different CI hardware.