Add circuit JSON download endpoint for debug page

[seveibar]

Summary

• add a /circuit_json endpoint that returns the generated circuit JSON and prefers compressed code when both sources are present
• expose a styled "Download Circuit JSON" link on the debug page that points to the new endpoint
• extend the debug page test to confirm the link and download behavior

Testing

• bunx tsc --noEmit
• bun test tests/debug-page.test.ts

---

https://chatgpt.com/codex/tasks/task_b_68ed34188e14832e9a3a4605e6d5e906

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Project	Deployment	Preview	Comments	Updated (UTC)
svg-tscircuit-com	Ready	Preview	Comment	Oct 13, 2025 5:38pm

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Preserve /api prefix in circuit JSON download link

The download URL is built from ctx.url and then its pathname is overwritten with /circuit_json. Because ctx.url has already had the /api prefix stripped for internal routing, this produces a link to /circuit_json instead of /api/circuit_json. In the deployed Next.js environment the API handler only lives under /api, so clicking the link rendered on /api?debug=1 will 404 and never reach the new endpoint, even though the Bun test passes (it serves the handler at /). The generated URL should retain the original request’s path prefix or explicitly add /api/circuit_json so the download works in production.

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