fix silkscreen text knockout rendering

[techmannih]

Summary

• Enable silkscreen text knockout polarity handling in the shared vector text Gerber renderer.
• Preserve text casing in Gerber output instead of forcing all vector text through toUpperCase().
• Refresh the silkscreen knockout repro snapshot and make the repro a normal passing test.
• Ensure requested silkscreen layers appear in the combined PCB + Gerber snapshot when pcb-stackup defines the layer group but does not include it in the rendered board body.

Root Cause

Silkscreen text used the shared vector text path, but knockout polarity was only enabled for copper text. Separately, the Gerber text loop uppercased every character before looking up glyph paths, which made lowercase source text render as uppercase in Gerber snapshots.

Validation

• bun test tests/gerber/generate-gerber-with-silkscreen-knockout-repro.test.ts

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
circuit-json-to-gerber	Ready	Preview, Comment	May 22, 2026 7:35am

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 6c1e1805b6

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[chatgpt-codex-connector]

Handle silkscreen injection independently per requested side

The guard enhancedSvg.includes(class="${silkscreenClass}") is global, so when both F_SilkScreen and B_SilkScreen are requested and neither is already rendered in the board body, the first injected side adds the shared ..._ss class and causes the second side to be skipped. This makes combined top+bottom silkscreen snapshots incomplete even though both layers were requested; the check should be tied to the specific side/group rather than any occurrence of the class.

Useful? React with 👍 / 👎.