fix: scope polling to widgets, fix retry, guard dates, throttle umami

- Remove global refetchInterval; scope to widget queries via setQueryDefaults
- Fix error boundary retry: correct queryKey to [["widget"]], move invalidation to onReset
- Add toValidDate() helper in @homarr/common for cache hydration safety
- Guard date formatting in media-releases and media-requests against non-Date values
- Set umami refetchInterval to 60s via shared umamiQueryOptions constant
- Simplify dns-hole mutations to invalidate() instead of manual optimistic setData

packages/api/src/query-cache.ts

@@ -1,7 +1,5 @@
 import type { QueryKey } from "@tanstack/react-query";
 
-// ponytail: staleTime 0 = always refetch on mount (fresh data every dashboard load).
-// refetchInterval 30s = poll while page is open. gcTime 24h = Redis TTL for persisted cache.
 export const queryCacheDefaultStaleTimeMs = 0;
 export const queryCacheDefaultRefetchIntervalMs = 30_000;
 export const queryCacheDefaultGcTimeMs = 1000 * 60 * 60 * 24;