[EagleFox31]

Why

The platform that provisions attractive, evidence-backed GitHub READMEs still displayed a plain, stale "M3 OpenPage POC" introduction. This PR makes AppFactory itself a first-class consumer of its existing reusable README content/presentation contract.

README modernization

• Product-specific centered hero, memorable tagline, 5 Shields.io badges and 8 real navigation links.
• A plain-language product case, Mermaid control-plane architecture, five-family blueprint catalog, quick start, verified security boundaries and RAIDER owner split.
• Distinguishes operational native/service paths from OpenPage POC and non-deployed generic presets.
• Preserves full existing detailed API, runtime, Cloudflare, brownfield and infrastructure documentation below the modernized introduction.

Reusable lifecycle, not hand styling

• Adds .appfactory/readme-contract.json: product semantics, capabilities with evidence and v2 presentation declaration.
• Makes the existing Product README Contract CI self-audit this README on changes, with fail-closed badge/anchor checks.
• Routes both README and manifest changes through documentation-only QA; does not trigger unnecessary runtime builds.
• Explicitly marked managed hero for idempotent future updates.

RAIDER acceptance

• Reuses shared renderer/auditor; no duplicate code.
• Product-agnostic presentation contract, product-owned copy.
• Non-destructive preservation of all operational documentation.
• Dedicated CI must pass including on-repo README audit.
• Merge only after required checks are green.

Scope: docs and CI classification only. No production infrastructure or API behavior changes.