feat(a2a): Introduce restore command for a2a server (#13015)

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
Co-authored-by: Shreya Keshive <shreyakeshive@google.com>

packages/a2a-server/src/config/config.ts

@@ -71,6 +71,9 @@ export async function loadConfig(
     ideMode: false,
     folderTrust: settings.folderTrust === true,
     extensionLoader,
+    checkpointing: process.env['CHECKPOINTING']
+      ? process.env['CHECKPOINTING'] === 'true'
+      : settings.checkpointing?.enabled,
     previewFeatures: settings.general?.previewFeatures,
   };