Ship question-type screenshots as a release asset (and regenerate them)

Start with uv run codegen --screenshots and the existing screenshots/<slug>/{limesurvey,xlsform}.png outputs, then inspect how cdl-survey-types-* and formtransform-fixtures-* release assets are generated. Add the versioned tarball and manifest.json, and implement the completeness check for registered entities and PNGs. Done means current-registry screenshots are regenerated, packaged as a release asset, and stale or missing files are detected without Docker.

screenshots/<slug>/{limesurvey,xlsform}.png render each registry type as a respondent sees it. Nothing consumes them yet, but the survey site wants exactly these: its fragetypen page has LimeSurvey and KoboToolbox tabs per example that currently say "Screenshot folgt" (CorrelAid/cdl-wp-eins, QuestionTypeBlock.astro). qwacback's examples are the registry fixtures (e.g. qwacback single_choice = registry/entities/select_one/fixtures/xlsform.json, pinned at v0.7.1), so the screenshots match them one to one.

Site-side proposal: CorrelAid/cdl-wp-eins#33.

State today

• Last generated in the initial commit (2026-08-05). The registry has changed a lot since, up to v0.7.1.
• range has no screenshots.
• Not in the npm package or the release assets. The only way to get them is the repo tree on main, which isn't versioned.

Proposal

1. Regenerate all screenshots against the current registry (uv run codegen --screenshots).
2. Release asset formtransform-screenshots-<version>.tar.gz, next to cdl-survey-types-* and formtransform-fixtures-*, with a manifest.json:

   {
     "version": "0.7.1",
     "types": {
       "select_one": {
         "limesurvey": { "file": "select_one/limesurvey.png", "width": 1930, "height": 758, "engine": "LimeSurvey", "theme": "fruity_twentythree" },
         "xlsform":    { "file": "select_one/xlsform.png",    "width": 1296, "height": 450, "engine": "Enketo" }
       }
     }
   }
   

   Width/height let consumers reserve layout space. engine makes clear the XLSForm shot is Enketo (the engine behind KoboToolbox web forms), not the Kobo UI itself.
3. Completeness check (in codegen or CI, cheap, no Docker): every registry entity (types, variants, composites) has both PNGs, and no PNG exists for a slug that isn't registered. That keeps them from going stale silently, the way range did.
4. Optional: note the registry version a screenshot was rendered from in the manifest, so a consumer can warn when it's older than the entity.

Consumers (planned)

• qwacback already pulls formtransform assets at its pinned version. It would unpack this tarball, serve /api/examples/{type}/limesurvey.png and /xlsform.png, and add limesurveySrc, koboSrc, dimensions and alt text to the example response. Example and screenshot then always come from the same registry version. Keyed by registry slug, which fits CorrelAid/qwacback#49.
• cdl-wp-eins renders what qwacback returns (CorrelAid/cdl-wp-eins#33).