feat: add pcb_courtyard_polygon and pcb_courtyard_circle to footprint TSX generation

[Kabi10]

Summary

Resolves tscircuit/tscircuit#1081 — "Make sure kicad component components create courtyards"

• Adds <courtyardpolygon> JSX output for pcb_courtyard_polygon circuit-json elements
• Adds <courtyardcircle> JSX output for pcb_courtyard_circle circuit-json elements
• Passes through optional attributes: strokeWidth, isFilled, hasStroke, isStrokeDashed, color for polygons; strokeWidth, color for circles

Before

All 4 courtyard types are already produced by kicad-component-converter and rendered by circuit-to-svg, but only pcb_courtyard_outline and pcb_courtyard_rect were being converted to TSX footprint elements. Polygon and circle courtyard shapes were silently dropped.

After

Full round-trip coverage for all 4 courtyard types:

circuit-json type	TSX element
pcb_courtyard_outline	<courtyardoutline> (existing)
pcb_courtyard_rect	<courtyardrect> (existing)
pcb_courtyard_polygon	<courtyardpolygon> ✨ new
pcb_courtyard_circle	<courtyardcircle> ✨ new

Test plan

• Added test("test8 support courtyard polygon and circle") verifying both new elements are emitted with correct attributes
• All 12 pre-existing passing tests still pass

/claim #1081

🤖 Generated with Claude Code

[Kabi10]

Context for reviewers:

PR #25 (merged 2026-03-06) added pcb_courtyard_outline and pcb_courtyard_rect to footprint TSX generation.

The kicad-component-converter already parses all 4 courtyard types from KiCad files (see convert-kicad-json-to-tscircuit-soup.ts lines 864-963 in main), but generate-footprint-tsx.tsx was never updated for the remaining two:

• pcb_courtyard_polygon -> no TSX element emitted (gap)
• pcb_courtyard_circle -> no TSX element emitted (gap)

This PR closes those two gaps, completing full round-trip coverage for all 4 courtyard types: KiCad file -> circuit-json -> TSX footprint.

[Kabi10]

Closing since tscircuit/tscircuit#1081 was closed as completed without a reward being issued. The implementation is correct and complete — happy to reopen if the bounty is revisited.