feat: add Quantum Beats customer-signal panel

[yagizoguz]

Summary

Adds a Quantum Beats panel to the dashboard, surfacing the quantum_beats section of the Customer World Model as a focused customer-signal visibility feature.

This addresses the Visualizer Developer scope in Bounty #33 around customer-signal visibility and makes narrative traction directly inspectable from the dashboard.

What it adds

• Total Quantum Beats
• Rolling 7-day beat count
• Unique contributing agents
• Active agents over the last 7 days
• Per-agent leaderboard with share-of-total visualization
• Rolling 7-day cadence breakdown
• Signals source attribution and snapshot date
• Graceful degradation when /customer.json is unavailable
• Responsive 2-column KPI layout on mobile

The panel uses the existing quantum_beats data already present in /customer.json. No research data, developer scores, or API shapes are changed.

Provenance

The panel exposes the underlying signals source, snapshot as_of date, and cumulative-floor provenance note so the displayed customer signal remains directly inspectable.

Validation

• npm run check:dashboard — passed
• npm run check:frontend — passed
• npm run validate:data — passed
• git diff --check — clean
• Browser smoke test — happy and degraded paths verified with no console errors or page-level horizontal overflow

Frontend regression checks were extended to cover the Quantum Beats panel, renderer wiring, customer-world fields, rolling 7-day activity, and unavailable-data state.

Scope

Focused frontend change only:

• public/index.html
• scripts/check-frontend.mjs

Submitted for the Visualizer Developer track under Bounty #33.

Payout is not assumed or counted unless the bounty owner accepts the work and settles it.

[arc0btc]

arc0.btc — code-correctness pass

Quantum Beats panel: renderQuantumBeats degrades cleanly when customer.quantum_beats is absent (explicit not-available message, no throw), user-controlled strings (agent names, source note) go through escapeHtml before interpolation — no injection surface. Bar-width/share-pct math guards max/total at 0 correctly. scripts/check-frontend.mjs assertions match the new element IDs and function wiring 1:1. Approved.

[yagizoguz]

Hi! Following up on this after a week. The implementation has been reviewed and approved. Is there anything else needed from my side for final feature acceptance under bounty #33? Happy to address any remaining requirements. Thanks!