Add repository-owned Control Program flows (#210)

* feat: add repository-owned control program flows

* fix: support Node 20 package resolution

* fix: close flow execution boundaries

* fix: harden flow authoring boundaries

* fix: make flow projection authorization durable

* fix: preserve flow identities and filesystem scope

* fix: preserve exact flow context

* fix: keep flow projections consumer-ready

* fix: compare projection modes portably

* fix: bind flow producer boundaries

* fix: preserve flow plan filename on resume

* fix: close flow projection trust boundaries

* fix: bind flow inputs exactly

* fix: bind flow execution invariants

Author: bigboateng