Fix 5 bugs: analytics range keys, stale visitor rows, NuggetsPage init state, episodes timer leak, unsanitized nuggets object; v2.0.1

- analytics: union byDayReal+byDayBot keys so bot-only days aren't dropped from range totals
- analytics: exclude timestamp-less visitor rows from range filters (was unconditionally including them)
- App.tsx: init `configured` to false so a network failure doesn't show a misleading "no episodes" state; add r.ok guard before r.json()
- episodes.js: wrap fetch in try/catch so clearTimeout is called on network failure, matching the nuggets.js pattern
- helpers.js: add sanitizeNuggets + wire it into sanitizeSiteContent so corrupted hosts/urls can't crash NuggetsPage

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

server/routes/episodes.js

@@ -14,15 +14,20 @@ export async function fetchAllEpisodes() {
   }
   const controller = new AbortController()
   const timeout = setTimeout(() => controller.abort(), 8000)
-  const response = await fetch(RSS_FEED_URL, { signal: controller.signal })
-  clearTimeout(timeout)
-  if (!response.ok) throw new Error(`RSS fetch failed: ${response.status}`)
-  const xml = await response.text()
-  rawXmlCache = xml
-  const episodes = parseRssItems(xml)
-  episodesCache = episodes
-  episodesCacheAt = now
-  return episodes
+  try {
+    const response = await fetch(RSS_FEED_URL, { signal: controller.signal })
+    clearTimeout(timeout)
+    if (!response.ok) throw new Error(`RSS fetch failed: ${response.status}`)
+    const xml = await response.text()
+    rawXmlCache = xml
+    const episodes = parseRssItems(xml)
+    episodesCache = episodes
+    episodesCacheAt = now
+    return episodes
+  } catch (err) {
+    clearTimeout(timeout)
+    throw err
+  }
 }
 
 export async function fetchRawFeedXml() {