Redo /newsletter and /nuggets pages; add Nuggets episode tags with admin editor; v2.37.0

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

server/state.js

@@ -96,6 +96,9 @@ export const state = {
   // newsletterIssues: Array<{ id, resendBroadcastId, slug, title, subject, description, html, sentAt, publishedAt, public }>
   newsletterIssues: [],
   newsletterIssuesWritePromise: Promise.resolve(),
+  // nuggetsEpisodeTags: { [audioUrl]: string[] } — admin-assigned tags for Nuggets RSS episodes
+  nuggetsEpisodeTags: {},
+  nuggetsEpisodeTagsWritePromise: Promise.resolve(),
 
 
   auditLog: [],