Summary

Fixes #5497.

• remove the hardcoded 2022 renewable-energy snapshot from the production recovery path
• persist only validated World Bank payloads and serve them as bounded last-known-good data for up to seven days
• version the breaker cache key so pre-fix entries that may contain the static snapshot are never reused
• expose live, cached, and unavailable states to the panel, including cache age
• prevent cached or unavailable renewable data from triggering happy-variant record celebrations

This is an alternative to #5521's disclosure-banner approach: the static fallback is deleted rather than retained and labelled.

Intent and non-goals

The intent is to preserve availability with canonical last-known-good data while failing closed when no trustworthy observation exists.

Non-goals:

• no direct browser-to-World-Bank fallback
• no bootstrap/KV deployment flag changes
• no generic circuit-breaker redesign
• no changes to the independent EIA capacity series

Validation matrix

Review gates

• Reviewed for cache integrity, stale-state races, failure semantics, and milestone side effects.
• A stale-while-revalidate race found during review was fixed by storing cache timestamps with each snapshot and classifying the returned object atomically.
• No unresolved review findings.

Documentation

Not applicable. This changes an internal recovery contract and reuses the existing panel data-badge convention.

Screenshots / UI evidence

Automated rendered-DOM coverage verifies the unavailable state renders no World Bank chart and the cached state displays cache age. No durable screenshot is attached.

CI and review follow-up

Pending after publication.

Residual findings

None.