Add release date and episode # columns to admin lesson list with inline date editing; use local time for release dates; v2.8.2

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

server/study-helpers.js

@@ -312,9 +312,11 @@ export function isSectionReleased(section) {
 
 export function redactUnreleasedSection(section) {
   if (!section || typeof section !== 'object') return section
-  if (isSectionReleased(section)) return section
+  // episodeNumber is an admin-only reference and is never sent to the public site
+  const { episodeNumber: _episodeNumber, ...publicSection } = section
+  if (isSectionReleased(section)) return publicSection
   return {
-    ...section,
+    ...publicSection,
     passageText: '',
     commentary: '',
     greekNotes: [],