feat: implement service filtering

If a user implements the user-auth-service trigger in a plugin and that plugin does not echo the passed in app(s) on stdout, the app is assumed to not exist. This mirrors the functionality for applications in regards to auth filtering.

This may still need auditing to ensure it covers everything and doesn't cause issues, but local testing implies that everything is working as expected.

post-app-rename-setup

@@ -8,8 +8,7 @@ set -eo pipefail
 plugin-post-app-rename-setup() {
   declare OLD_APP_NAME="$1" NEW_APP_NAME="$2"
 
-  local SERVICES=$(ls "$PLUGIN_DATA_ROOT" 2>/dev/null)
-  for SERVICE in $SERVICES; do
+  for SERVICE in $(fn-services-list false); do
     if in_links_file "$SERVICE" "$OLD_APP_NAME"; then
       add_to_links_file "$SERVICE" "$NEW_APP_NAME"
     fi