Template and plugin marketplaces

[karutoil]

Summary

Create browsable marketplaces for templates (server eggs) and plugins, allowing the community to share and discover content. This is the long-term evolution of the current Egg Explorer plugin and manual plugin installation.

Current State

• Templates: 248 Pterodactyl eggs in-repo, importable via API or Egg Explorer plugin. No sharing/discovery beyond this repo.
• Plugins: 3 built-in plugins (example, ticketing, egg-explorer). Manual installation via filesystem. Plugin SDK exists with catalyst-plugin create scaffold.
• No central registry, versioning, or distribution mechanism for either templates or plugins.

Requirements

Template Marketplace

• Browse community-submitted templates with search, category filters, and ratings
• One-click import into the user's installation
• Template versioning (authors can push updates, users can opt-in to updates)
• Template validation on submission (must pass egg import conversion)
• Author profiles and template statistics (downloads, servers using it)

Plugin Marketplace

• Browse community plugins with install/uninstall from the admin panel
• Plugin versions with compatibility checks against the Catalyst version
• Automated install: download plugin bundle → extract to plugins dir → hot-reload
• Plugin metadata: description, screenshots, permissions required, author
• Review/rating system

Shared Infrastructure

• API endpoints for marketplace browsing, search, and installation
• Package format: tarball/zip with plugin.json manifest (plugins) or egg JSON (templates)
• Signature verification for marketplace packages (optional but recommended)
• Admin settings: enable/disable marketplace, allowed categories, approval workflow

Acceptance Criteria

• Template marketplace API: browse, search, import, version check
• Plugin marketplace API: browse, install, uninstall, update
• Frontend admin pages for both marketplaces
• Plugin install triggers hot-reload without backend restart
• Compatibility checks prevent installing incompatible plugins/templates
• Package signature verification (at least basic integrity check)