Plugin support for dcode.
Add a local marketplace to dcode state.
Add a marketplace from a pasted source string.
Discover enabled marketplace plugins from their install cache paths.
Install a marketplace plugin into the versioned cache and enable it.
Copies the plugin source into plugins/cache/{marketplace}/{plugin}/{version}/,
writes installed_plugins.json, and enables the plugin.
List plugins from configured marketplaces.
Return plugin ids that have install records.
Remove a marketplace and every plugin installed from it.
Local marketplace source directories are never deleted. Managed marketplace clones and installed plugin caches are removed.
Set the enabled state of an installed plugin.
Uninstall a plugin (disable, clear records, delete orphaned cache).
State storage for dcode plugin marketplaces, installs, and enablement.
Variable substitution for plugin-provided configuration.
Plugin discovery, install, and enablement helpers.
Plugin manifest parsing for plugins.
CLI helpers for plugin management.
Marketplace parsing for plugins.
Data models for plugins.
Plugin subsystem adapters.
