Improve metrics clarity, exploration, and refresh reliability

src/routes/metrics/+page.server.ts

@@ -1,7 +1,7 @@
 import { readMetrics } from '$lib/server/fleet/metrics.js';
+import { parseMetricsDays } from '$lib/metrics.js';
 import type { PageServerLoad } from './$types';
 
 export const load: PageServerLoad = ({ url }) => {
-    const requested = Number(url.searchParams.get('days') ?? 7);
-    return readMetrics([1, 7, 30].includes(requested) ? requested : 7);
+    return readMetrics(parseMetricsDays(url.searchParams.get('days')));
 };