Roadmap: resumable run manifest and proof-receipt history

## Goal

Resume interrupted CodeCanopy work without repeating accepted subtrees or losing the evidence used for parent acceptance.

## Evidence gate

Implement this only after real Recursive Canopy runs show that the current in-session contract loses useful work across interruption or compaction.

## Candidate scope

- A small append-only run manifest with node IDs, states, baselines, dependencies, produced artifacts, checks, and proof receipts.
- Resume validation that rejects stale baselines, dirty path collisions, missing artifacts, or weakened authority.
- Critical-frontier reconstruction from accepted dependencies.
- Explicit invalidation of only affected descendants.
- Human-readable inspection without a database or dashboard.

## Non-goals

- No daemon, telemetry platform, distributed queue, or hosted control plane.
- No automatic trust of old checks after source or dependency drift.
- No storage of credentials or full conversation transcripts.

## Acceptance

A stopped sample run resumes from the smallest valid frontier, accepted unrelated nodes remain accepted, and root verification still runs on the final integrated state.