chore: restore cadence app entry

[cdransf]

Description

Change of heart — Cadence development will continue and the app is now free.

Type of change

• App catalog entry (new app or update) — fill in the section below
• Documentation
• Bug fix
• Styling / layout
• Other

Checklist

• The build passes (npm run build)
• I previewed my changes locally (npm start) when relevant

📱 Adding or updating an app in the catalog?

Guide: https://www.navidrome.org/docs/developers/adding-apps/

• App supports the OpenSubsonic, Subsonic, or Navidrome API
• Folder under assets/apps/ uses kebab-case (e.g. my-awesome-app)
• index.yaml has all required fields: name, url, platforms, api, description, screenshots.thumbnail
• Thumbnail is a real screenshot of the app (not a logo or icon)
• Images are WebP, max 1200px, under 500KB each (npm run convert:images <app-name>)
• npm run validate:app <app-name> passes
• I'm the app's author/maintainer, or have permission to submit it

[strix-security]

Strix Security Review

No security issues found.

_{Updated for b9fff26.}

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Reviewed by Strix
_{Re-run review · Configure security review settings}

[github-actions]

App Validation Results

Validation run: 2026-08-23 18:14:30 UTC

---

Validating: cadence

App: cadence
Status: FAILED ❌


Warnings (1):
  1. App URL returned status 404: https://www.coryd.dev/posts/2025/i-made-a-music-app

✅ Validation passed

---

✅ All validations passed!

[github-actions]

Preview Deployment

Status	URL
✅ Deployed	pr-428.navidrome-website.pages.dev

Built from b9fff26