feat(mindspace): gate published page delivery

mindspace-public-finish-sync.mjs

@@ -429,6 +429,19 @@ export function materializePublicHtmlWritesFromSessionEvent(
   return { materialized: [], skipped: [] };
 }
 
+/** Read the public HTML targets from a stream event without writing them. */
+export function collectPublicHtmlWritePathsFromSessionEvent(event, { publishDir, recentCount = 20 } = {}) {
+  if (!event || !publishDir) return [];
+  const messages = event.type === 'Message' && event.message
+    ? [event.message]
+    : event.type === 'UpdateConversation' && Array.isArray(event.conversation)
+      ? event.conversation.slice(-Math.max(1, recentCount))
+      : [];
+  return [...new Set(extractPublicHtmlWriteArtifacts(messages, { publishDir })
+    .map((artifact) => artifact.relativePath)
+    .filter(Boolean))];
+}
+
 function messageHasPublicHtmlToolRequest(message, { publishDir = null } = {}) {
   if (extractPublicHtmlWriteArtifacts([message], { publishDir }).length > 0) {
     return true;