forked from 1b-agent/opencadstudio-upstream
OpenCADStudio no longer bundles plugins — every add-on is an external cdylib loaded from the plugins folder or installed via the marketplace. - Remove the demo plugin and the in-tree ocs_example_plugin crate. - Remove the inventory-based built-in registration path (PluginRegistration, all_plugins, installed_manifests); registry now serves core ribbon tabs plus loaded external plugins, and try_dispatch routes only to externals. - Plugin Manager drops the 'compiled into this build' section; the enable/disable toggle moves onto loaded external cards. - Prune the now-dead HostSession/DocumentTab helpers and re-exports. Part of the #100 extensibility epic (phase 2). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>