feat(shared): Tier 3 wave 2 (12 components) + self-hosted fonts

Two changes in one commit because they were prepared together and the
component demos depend on the new self-hosted fonts.css.

Tier 3 wave 2 — 12 new components
---------------------------------
Adds components-tier3-supplement.css (886 lines) and 12 isolated demo
HTML pages under shared/playground-examples/components/:
toxic-flow chain, fleet-overview, kanban Keep/Review/Remove,
maturity-ladder, classify-and-transform, cycle-ribbon,
persistent-antipattern, suppressed-signals, ExpansionCard, ReadMore,
FormProgress, Aspirational-vs-Committed.

Reuses existing tokens — no new CSS custom properties. Honors the
Phase 1 feedback rules: no large pink areas for body text, severity-red
distinct from failure-red, dark mode via existing [data-theme="dark"].

Provenance: components-tier3-supplement.css and the 12 demo bodies were
authored by claude.ai/design (separate Anthropic instance) on 2026-05-03.
This commit only integrates them — path rewrites, font swap, generic
name substitution in fleet-overview demo data, README updates.
base.css from the export was deliberately NOT taken in because it
reverted the inline-message contrast fix from v0.1.

Self-hosted fonts (Inter, JetBrains Mono, Source Serif 4)
---------------------------------------------------------
Replaces all fonts.googleapis.com / fonts.gstatic.com requests with
.woff2 files bundled at shared/playground-design-system/fonts/.

Why:
- No data leaked to Google about end-user IPs and User-Agents.
- GDPR-safe for Norwegian public-sector deployments.
- Works offline / behind air-gapped firewalls.
- Forkers downloading the marketplace get a complete bundle.

All three families are SIL Open Font License 1.1 — license texts
included alongside the woff2 files. Source Serif 4 woff2 generated
locally from the upstream OTF release using
fonttools ttLib.woff2 compress; Inter and JetBrains Mono are
unmodified upstream webfont releases.

Total bundle: 9 woff2 files, ~940 KB. New fonts.css declares all
@font-face rules with font-display: swap. All 6 example HTMLs and 12
new component demos load it via a single relative path.

Verified
--------
- Privacy grep returns empty across plugins/ and shared/
- Google Fonts grep returns empty across shared/*.html
- Smoke test via python -m http.server: HTML + 7 stylesheets +
  Inter-Regular.woff2 all return 200

Doc updates
-----------
- shared/playground-design-system/README.md: file tree updated,
  Quick start snippet shows fonts.css link, "Self-hosted fonts"
  section added
- shared/playground-design-system/fonts/LICENSES.md: combined attribution
- README.md (root): Tier 3 wave 1+2 component list, Privacy-first bullet
- CLAUDE.md (root): tree entry expanded for new components + fonts

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

shared/playground-examples/index.html

@@ -8,9 +8,7 @@
 <link rel="stylesheet" href="../playground-design-system/base.css" />
 <link rel="stylesheet" href="../playground-design-system/components.css" />
 <link rel="stylesheet" href="../playground-design-system/components-tier2.css" />
-<link rel="preconnect" href="https://fonts.googleapis.com">
-<link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
-<link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600&family=Source+Serif+4:wght@400;600&display=swap" rel="stylesheet">
+<link rel="stylesheet" href="../playground-design-system/fonts.css" />
 <style>
   .hero { padding: var(--space-16) 0 var(--space-12); border-bottom: 1px solid var(--color-border-subtle); background: var(--color-bg-soft); }
   .hero__eyebrow { font-size: var(--font-size-xs); text-transform: uppercase; letter-spacing: 0.12em; color: var(--color-text-tertiary); font-weight: var(--font-weight-semibold); margin-bottom: var(--space-3); }