Improve crash stats dashboard UI / 优化崩溃统计面板 UI

[SivanCola]

Summary

• Add a header language switcher for Chinese and English, persisted locally in the browser.
• Add y-axis tick labels, gridlines, and wider hover targets to the daily active installs chart.
• Redesign crash filters into grouped status and facet chips that handle long version labels cleanly.
• Redesign crash groups as row-level clickable diagnostic cards with clearer scope, health, and count columns.
• Redesign crash group detail pages with a compact summary header, key metrics, collapsible samples, copy actions, and a tighter admin management layout.

Verification

• Worker TypeScript typecheck passed.
• git diff --check passed.
• Verified the stats dashboard and crash group detail page in the in-app browser with local previews.
• Verified Chinese/English switching, sample expansion, row-level navigation targets, and copy-button success/failure states.

Cache impact

• No prompt-cache or provider-visible request surface changes; this only affects the crash stats Worker UI.