feat: added help command

internal/plugin/plugin.go

@@ -47,6 +47,13 @@ func GetAvailablePlugins() map[string]model.Plugin {
 	return result
 }
 
+// ClearRegistry clears all registered plugins (for testing)
+func ClearRegistry() {
+	pluginsMu.Lock()
+	defer pluginsMu.Unlock()
+	plugins = make(map[string]model.Plugin)
+}
+
 // BasePlugin provides a common base for plugins
 type BasePlugin struct {
 	ID             string