fix: refresh Pages viewer once per minute

[xudaniel]

Summary

• refresh private API and demo data once every 60 seconds instead of every 10 seconds
• label the battery card as SYNTHETIC DATA in demo mode and LIVE DATA in connected mode
• update English and Chinese documentation to match the one-minute heartbeat cadence
• bump the service-worker cache so existing installations receive the correction

Why

The public GitHub Pages app defaults to synthetic demo readings. The observed 85 percent value was not a sensor reading; the current Mac health check reports 100 percent. The stronger label prevents synthetic values from being mistaken for live telemetry.

Verification

• Pages application tests: 5 passed
• JavaScript syntax: passed
• bilingual documentation checks: passed
• desktop visual rendering: passed
• exact refresh assertion: 60,000 ms

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Advance heartbeat status between minute polls

With this interval increased to 60 seconds, the server-supplied age_seconds and overall values rendered by render() remain frozen until the next request. If a heartbeat is missed shortly after a successful refresh, the viewer can continue showing “Awake & protected” for nearly a minute after the 90-second offline threshold has passed, whereas the previous delay was at most about ten seconds. Keep the network polling at one minute but advance the displayed age and derive stale/offline state locally between polls.

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