Dev: Fix useExhaustiveDependencies — Weather Toolkit

[conbrad]

Describe the task
Remove biome-ignore lint/correctness/useExhaustiveDependencies comments and properly fix dep arrays in the Weather Toolkit hook and page.

Acceptance Criteria

• Remove biome-ignore comment from apps/wps-web/src/features/weatherToolkit/hooks/useWxChartCache.ts (line 42 — cache reset effect)
• Remove biome-ignore comment from apps/wps-web/src/features/weatherToolkit/pages/WeatherToolkitPage.tsx (line 30)
• yarn biome lint passes with zero useExhaustiveDependencies errors on both files
• Scrubbing through forecast hours loads charts correctly
• Changing model type or run hour resets the cache (no stale images from previous model)

Additional context

• The prefetch and unmount cleanup effects in useWxChartCache.ts are already correct — only the cache reset effect at line 42 needs attention.