fix: preserve context window during resume preset refresh (#1353)

Co-authored-by: Letta Code <noreply@letta.com>

src/headless.ts

@@ -918,6 +918,7 @@ export async function handleHeadlessCommand(
             agent.id,
             presetRefresh.modelHandle,
             resumeRefreshUpdateArgs,
+            { preserveContextWindow: true },
           );
         }
       }