Switch connection string encoding from the old base64 blob to a readable sk1:// URL format (host/token[?exp&insecure]) across agent, backend, and frontend. Update encode/decode logic and extensive tests to validate port preservation, insecure/http handling, expiry parsing, and input validation; adjust agent pairing UI to accept the new scheme. Add ServerKit Agent GUI plugin: backend blueprint endpoints for capabilities, frame capture and synthetic desktop, plugin metadata; frontend plugin components (ServerGui, Launcher, SyntheticDesktop), styles, and manifest entry to enable streaming screenshots with a synthetic fallback. Also add Windows service stop waiting to avoid start races after pairing, and document SERVERKIT_PUBLIC_URL in env examples.
Introduce a plugin installation and management system.
Backend: add InstalledPlugin model, plugin_service with download/install/enable/disable/uninstall, dynamic blueprint registration and frontend manifest generation, and plugins API endpoints (list/get/install/enable/disable/uninstall). Register plugins blueprint and attempt to hot-load installed plugin blueprints at app startup.
Frontend: add PluginLoader component (Vite import.meta.glob) to render plugin widgets, extend Marketplace UI to install/manage plugins, add API client methods for plugins, and update styles for the marketplace plugin UI. This enables installing plugins from GitHub/repos/zips and managing them from the app.
Juan Denis