Provisioning: Adds support for enabling app plugins (#25649)

Adds support for enabling app plugins using provisioning. 

Ref #11409

Co-authored-by: Arve Knudsen <arve.knudsen@gmail.com>
Co-authored-by: Diana Payton <52059945+oddlittlebird@users.noreply.github.com>

pkg/plugins/queries.go

@@ -85,3 +85,9 @@ func GetEnabledPlugins(orgId int64) (*EnabledPlugins, error) {
 
 	return &enabledPlugins, nil
 }
+
+// IsAppInstalled checks if an app plugin with provided plugin ID is installed.
+func IsAppInstalled(pluginID string) bool {
+	_, exists := Apps[pluginID]
+	return exists
+}