feat(migration): migrate legacy owner data and update config reference handling

- Implemented a migration process to move resources from the legacy owner "default" to the new default owner "local", ensuring no data loss during the transition.
- Updated configuration reference handling to replace legacy `$VAR_`, `$SECRET_`, and `$CONTEXT_` prefixes with mustache-style `{{ vars.name }}`, `{{ secrets.name }}`, and `{{ context.name }}`.
- Enhanced YAML configuration files and scripts to reflect the new mustache syntax, improving consistency across the application.
- Added tests to validate the migration process and ensure proper handling of legacy references.
- Updated documentation to guide users on the new configuration reference format.

packages/server/config-ref-rewrite.js

@@ -0,0 +1,17 @@
+/**
+ * Rewrite legacy `$VAR_` / `$SECRET_` / `$CONTEXT_` placeholders to mustache.
+ * Safe for passwordSecret-style fields (those store bare names, not $SECRET_ prefixes).
+ *
+ * @param {string} text
+ * @returns {{ text: string, changed: boolean }}
+ */
+export function rewriteLegacyConfigRefsInText(text) {
+  if (typeof text !== "string" || text.length === 0) {
+    return { text: text ?? "", changed: false };
+  }
+  const next = text
+    .replace(/\$VAR_([A-Za-z0-9._-]+)/g, "{{ vars.$1 }}")
+    .replace(/\$SECRET_([A-Za-z0-9._-]+)/g, "{{ secrets.$1 }}")
+    .replace(/\$CONTEXT_([A-Za-z0-9._-]+)/g, "{{ context.$1 }}");
+  return { text: next, changed: next !== text };
+}