Publish on apps.nextcloud.com (app store submission)

[Jaggob]

Get the app published on https://apps.nextcloud.com so admins can install via NC's built-in app discovery instead of manually unpacking a tarball.

This is a multi-step process — opening as an epic with sub-tasks. Most steps are one-off but each blocks the next.

Sub-tasks

• Claim the etherpad_nextcloud app ID on apps.nextcloud.com. Confirm we own the slug; rename if it's taken.
• Generate the code-signing keypair per NC's instructions: 4096-bit RSA, the public key is registered on apps.nextcloud.com, the private key signs every release tarball. Store the private key safely (1Password / equivalent).
• Sign the existing release tarball for v1.1.0-alpha.1 (or whatever the next release is). Verify the signature locally before submitting.
• Capture 1–3 screenshots of the app in real use:
  • Files-app view with a .pad open in the native viewer
  • Admin settings panel
  • + → New pad flow / template picker
  • Public-share view (optional)
  • Recommended size: 1920×1080 PNG, dark + light theme variants if possible.
• Write the App Store description (English + German at minimum). 1–2 paragraphs explaining what the app does, target audience, and the Etherpad-server requirement. Keep it factual, no marketing copy.
• Set the listed categories (likely productivity, office, tools).
• Submit for review with the signed tarball URL pointing at the GitHub release. NC App Store moderation typically takes 1–2 days.
• Handle review feedback if anything is flagged — security, licensing, manifest issues.

Non-goals

• Marketing / outreach beyond the App Store listing.
• Backporting to NC < 31 (out of info.xml compat declaration).

Dependencies

• LICENSE file at repo root ✅ (already shipped in v1.1.0-alpha.1).
• A stable (non-alpha) version stamp. Probably the actual submission happens for the first 1.1.0 (non-alpha) tag, not the alpha.

Acceptance

• apps.nextcloud.com/apps/etherpad_nextcloud page exists and is approved.
• Admins can install via NC's app discovery / "+ Get apps" flow on a clean NC30+ instance.
• Signing key documented in a private location (not in this repo); release pipeline knows where to fetch it.