feat: make the attention-router value visible

[veil-chow-fyaic]

Outcome

Makes the product claim visible and executable: no copy/paste relay, no model polling, and no silent active-session takeover.

• adds modeled workflow accounting: manual lower bound 9 user actions versus 1 ThreadMesh kickoff;
• adds an active-receiver checkpoint case with zero steer, interrupt, or native-turn starts;
• publishes a generated 76-second MP4/GIF walkthrough based on fresh demo output and retained real Codex evidence;
• rewrites the English and Chinese README around user pain and honest evidence boundaries;
• adds the measured baseline protocol, non-interruption guide, 15-minute external operator challenge, and issue form;
• updates status, community signals, roadmap, and mainline freeze.

Claim boundary

The workflow accounting is modeled, not a human timing or token study. The retained real Codex run proves session behavior but used simulated Git/verifier effects. Real-effects integration is merged on main, while a fresh combined live run remains blocked by a reproducible network-invalid Codex endpoint. No DNS/TLS bypass was used.

Validation

• npm test: 384 tests, 55 schema cases, 7 transition cases, 112 Markdown files with zero lint findings
• npm run demo:assets: builder reruns the JSON demo and asserts the evidence contract
• MP4 and GIF: 76 seconds; all eight frames visually inspected
• real-product preflight recorded; no invalid live run started

Progresses #91 and #79 without closing either adoption or live-product gate.