forked from 1b-agent/opencadstudio-upstream
Add a Plugin Manager marketplace that installs external add-ons from a GitHub repo's Releases. A curated registry (plugins/registry.json in this repo, extended by PR) lists discoverable plugins; the host fetches it, shows each entry with a release dropdown, and on install downloads the asset matching the user's platform plus plugin.toml into the plugins folder (API-version checked first). Users can also link arbitrary owner/repo manually. Linked repos persist in settings. Desktop only (ureq + serde_json); the install path reuses the phase-2 loader. Part of the #100 extensibility epic (phase 2). Co-Authored-By: Claude Opus 4.8 <[email protected]>