Initialize the site's GitHub Copilot harness

[nicholasdbrady]

The site had detailed Copilot guidance, but no canonical cross-surface source of truth, no deterministic checks for fragile static-site contracts, and no disciplined delivery team for taking visual work from product framing through independent release review. This initializes a focused harness for GitHub Copilot app/CLI and VS Code agent mode while preserving the site's dependency-free architecture.

What changed

• Makes AGENTS.md the canonical repository guidance and reduces .github/copilot-instructions.md to a thin adapter.
• Adds path-scoped static-site instructions for shared navigation, Lucide, showcase scenes, mobile behavior, accessibility, and reduced motion.
• Adds a five-agent delivery team with exactly one user-invokable contact:
  • Site Director coordinates all work and owns the product-positioning, visual-world, and merge approval gates.
  • Hidden Product Shaper owns PM, product truth, scope, and PRODUCT.md.
  • Hidden Experience Designer owns Impeccable-led direction, critique, DESIGN.md, and a product-specific anti-slop contract.
  • Hidden Frontend Engineer owns production implementation, responsive craft, and post-implementation detector remediation.
  • Hidden Release Auditor independently blocks UI changes that fail accessibility, responsiveness, performance, implementation-integrity, approved-design, or anti-slop checks.
• Makes anti-slop a separate blocking verdict: the auditor runs the Impeccable detector, verifies every finding in rendered context, and also reviews generic composition and synthetic copy patterns the static detector cannot see.
• Adds machine-checkable agent visibility, tooling, anti-slop, and routing contracts to prevent team drift.
• Adds a dependency-free validator for local links/assets/fragments, shared nav/footer parity, documentation redirects, and showcase scene consistency.
• Runs agent-team and site validation in GitHub Actions, with external Taskbean/docs endpoint availability kept non-blocking.
• Clarifies product and documentation ownership in the README: taskbean/taskbean is product truth and taskbean/docs owns canonical docs.

Non-obvious boundaries

The director coordinates rather than editing. Hidden specialists remain programmatically invokable but do not appear as user entry points. Every UI-changing branch requires both independent release-readiness PASS and anti-slop PASS before the director requests merge approval. Detector output is evidence rather than an automatic verdict: false positives and deliberate exceptions require a concrete product or composition reason. Impeccable onboarding requires PRODUCT.md, followed by DESIGN.md, before replacement visual-world work.

The legacy in-repo docs/ tree is intentionally retained as a temporary migration source. It should be removed only after the separate taskbean/docs migration is merged and docs.taskbean.ai is verified.

Validation

• node scripts/validate-agent-team.mjs
• YAML parse of all five .agent.md profiles
• node scripts/validate-site.mjs
• node scripts/validate-site.mjs --check-external
• git diff --check