feat(ui): check-run details-page readiness table (visual)

[JSONbored]

Render the readiness table on the GitHub App check-run details page (#576), gated by the existing checkRunDetailLevel, reusing buildPublicReadinessScore output. Single scannable table slice; public-safe. Distinct from #576's collision-cluster table — this is the readiness-score table only.

Deliverables

• Readiness table component consuming buildPublicReadinessScore output (grep src/ for buildPublicReadinessScore)
• Render only at/above the configured checkRunDetailLevel; hide otherwise
• Public-safe: bands/labels, no raw credibility or reward fields
• Vitest test: detail-level shows table, below-level hides it, empty readiness set (both gate branches)

References

• apps/gittensory-ui/src/routes/app.maintainer.tsx
• apps/gittensory-ui/src/components/site/control-primitives.tsx:90
• src/review/stats.ts

Part of #576.

---

📸 Required: before/after screenshots (this is a UI change)

Non-negotiable. PRs that change UI must include a before/after screenshot table. PRs without it are automatically closed — no exceptions.

Rules:

• Show every page/feature you changed — before and after, one row each.
• Use the markdown table below. Screenshots go inside the table only — no large full-size images pasted elsewhere in the PR.
• Each cell is a clickable thumbnail (a small image linking to the full-size image) with a one-line caption underneath.
• Upload screenshots to the PR by drag-and-drop (GitHub hosts them on its CDN). Do NOT commit image files to the repo.

Copy this and fill it in (replace FULL_IMAGE_URL with the URL GitHub gives you after you drop the image in):

| Page / Feature | Before | After |
|---|---|---|
| `/your-route` | [<img src="FULL_IMAGE_URL" width="260">](FULL_IMAGE_URL)<br><sub>before: short caption</sub> | [<img src="FULL_IMAGE_URL" width="260">](FULL_IMAGE_URL)<br><sub>after: short caption</sub> |

---

---

size: S · held for later release (gittensor:feature once activated)

[linear-code]

JSO-2317