Epic: delete a bespoke multi-actor shared-state harness using Humanish

[danielgwilson]

Goal

Prove that Humanish can replace a bespoke multi-actor shared-state harness with Humanish core plus a thin adopter-owned adapter while retaining decision-equivalent evidence.

Shipped core

• Multi-lane fan-out: Multi-lane fan-out for the computer-use lab (proof-roadmap layer 2) #163 / 0.9.0.
• Sequential and concurrent shared-world: Multi-actor shared-world (shared-service) topology (proof-roadmap layer 7) #164 / 0.10.1.
• Computer-use scoring and feedback adapter seam: Adapter scoring/feedback hook on the computer-use (browser) route #165.
• Local-tree subject provisioning: 0.14.0.

Still unproven

• No adopter has completed a green deletion branch that removes its bespoke generic harness.
• Multi-origin shared-world remains ratified but gated in GATED: Add multi-origin apps and per-lane provenance to shared-world runs #239.
• First-class PII/PHI detection remains Add a first-class PII/PHI detector to the redaction gate #108 and becomes required before real-data subjects enter scope.

Acceptance

If a real adopter runs its accepted multi-actor proof families through current Humanish and a green deletion branch removes the generic bespoke run/history/Observer machinery, leaving only product-specific preparation, scenarios, state proof, scoring, and feedback, this epic is complete.

Do not close this from core capability tests alone.