Define detached runtime delivery

[djgrant]

This RFC defines a proposed boundary for running reconciliation without importing the original infrastructure program.

The document gives the proposal a concrete first consumer: a local runtime host. It covers the deployment bundle, resource manifests, actuator bindings, convergence, compatibility, and delivery stages.

The formats and APIs are not yet settled. The acceptance criteria keep them internal until a detached host can restart, update, and destroy a deployment from stored bundle data alone.

This RFC was split from #25 because the current reconciler delivery is implemented, while detached execution remains a separate proposal.

Checks

• pnpm build
• pnpm test:once