Stats: range buttons follow the retention settings

The Statistics page offers only the ranges kept (longest of the minute,
hour and day retentions), adds 1y and 2y when the daily data covers them,
caps the heatmap at the hourly retention and links to Explore within
retention.queries. Status and explore send retention_seconds. The query
log error names stats.retention.queries.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/web/static/assets/pages/explore.js

@@ -16,6 +16,13 @@ const filterWords = { client: "client", name: "name", domain: "domain", view: "v
 const keys = Object.keys(filterWords);
 const ranges = [["1h", 3600], ["6h", 6 * 3600], ["24h", 86400], ["3d", 3 * 86400], ["7d", 7 * 86400], ["30d", 30 * 86400]];
 
+// exploreRange is the longest range here of at most secs ("1h" at least).
+export function exploreRange(secs) {
+  let out = "1h";
+  for (const [k, s] of ranges) if (s <= secs) out = k;
+  return out;
+}
+
 // exploreHref is the explore page for these filters (and range).
 export function exploreHref(filters, since) {
   const q = new URLSearchParams();
@@ -74,7 +81,7 @@ export async function render(el, params, query) {
   }
 
   const parts = [head(f, go, since, ex), filterBar(f, since, ex, allViews)];
-  const maxSecs = retentionSecs(ex.retention);
+  const maxSecs = ex.retention_seconds || 7 * 86400;
   parts.push(h("div", { class: "filter-row", role: "group", "aria-label": "Time range" },
     h("span", { class: "muted" }, "Range"),
     h("div", { class: "segmented" }, ranges.filter(([, s]) => s <= maxSecs).map(([k]) =>
@@ -234,9 +241,3 @@ function stepWord(s) {
   if (s % 3600 === 0) return s === 3600 ? "hour" : s / 3600 + " hours";
   return s === 60 ? "minute" : s / 60 + " minutes";
 }
-
-function retentionSecs(r) {
-  const m = /^(\d+)([dhm])$/.exec(r || "");
-  if (!m) return 7 * 86400;
-  return Number(m[1]) * { d: 86400, h: 3600, m: 60 }[m[2]];
-}