fix(workflow): execute orchestration in the sandboxed PTC runtime

packages/README.md

@@ -51,7 +51,7 @@ Every package lives in exactly one group; new packages join existing groups, and
 | [`subagent/`](subagent/README.md) | Subagent capability family: provider-registry contract and model-facing delegation tools |
 | [`jobs/`](jobs/README.md) | Generic background-job runtime and model-facing job control tools |
 | [`experimental/`](experimental/README.md) | Pre-stable prototypes with explicit private exceptions |
-| [`workflow/`](workflow/README.md) | Workflow seam, worker-thread engine, and model-facing `workflow`/`ralph` tools |
+| [`workflow/`](workflow/README.md) | Workflow seam, PTC process engine, and model-facing `workflow`/`ralph` tools |
 | [`webhook/`](webhook/README.md) | Verified external events, trusted rules, and fire-and-forget Workspace Sessions |
 | [`web/`](web/README.md) | Web capability family: seam, search/fetch providers, model-facing web tools |
 | [`attachment/`](attachment/README.md) | Durable attachment identity, validation, local content-addressed storage |