Add session-to-prose OpenProse example

[rawwerks]

Summary

Adds a bundled session-to-prose OpenProse example under skills/open-prose/examples/.

The example turns local Claude Code, Codex, or Pi session logs into reusable Contract Markdown programs. It includes:

• a V5 src/session-to-prose.prose.md system with 15 services
• baseline-aware quality-regression-gate support via baseline-run
• receipt, harness, source-provenance, and tail/citation audit outputs
• workspace-only raw session retention with committed runs/, state/, deps/, and dist/ scaffolding
• an examples catalog entry and focused example README

Development Notes

This was developed through an iterative local evaluation loop. The submitted V5 contract is a hybrid of the two strongest earlier versions:

• V3 served as the generated-program/report quality floor because it produced the most concrete workflow programs and reports.
• V4 served as the receipt/harness/tail-audit floor because it added stronger run-envelope, result-contract, source-provenance, and tail-citation surfaces.
• V5 combines those two goals and adds a first-class quality-regression-gate so future runs can reject generated-program/report regressions while preserving the stronger receipt envelope.

After a six-session local audit, I added a follow-up hardening commit so the example explicitly rejects:

• summary-only manifests without per-service input/output and root-return mappings
• receipt audits that record missing self-published audit outputs while reporting no blocking issues
• stale V3/V4 provenance being labeled as current invoked-contract provenance
• recovered probe/write/SIGKILL events that are not propagated into final warning surfaces
• generated-service citation coverage that is satisfied only by a file-level provenance citation

Local run receipts and source session logs are intentionally not committed.

Validation

• git diff --check passed.
• prose lint skills/open-prose/examples/session-to-prose/src/session-to-prose.prose.md passed via the in-session OpenProse lint path.
• prose preflight skills/open-prose/examples/session-to-prose/src/session-to-prose.prose.md passed via the in-session OpenProse preflight path.
• safe-push public-repo reviewer approved the branch twice and found no secrets or private data leakage.
• Local V5 proof loop ran against six sessions: 2 Pi, 2 Claude Code, and 2 Codex. All six final V5 receipts reached complete-with-warnings with the expected eight logical outputs. The warning status is expected because nested prose CLI invocation is intentionally blocked inside the wrapper, so validation uses the in-session OpenProse VM path rather than recursively shelling out.

Notes For Reviewers

The example documents ~/.claude, ~/.codex, and ~/.pi session locations generically. No absolute local paths, session logs, run receipts, or generated internal artifacts are included in this branch.