[claude] Add session export as markdown (#288) (#304)

Co-authored-by: Claude (Opus 4.6) <claude@hermes.local>
Co-committed-by: Claude (Opus 4.6) <claude@hermes.local>

app.js

@@ -1223,9 +1223,66 @@ window.addEventListener('player-left', (/** @type {CustomEvent} */ event) => {
   console.log('Player left:', event.detail);
 });
 
+// === SESSION EXPORT ===
+/** @type {{ ts: number, speaker: string, text: string }[]} */
+const sessionLog = [];
+const sessionStart = Date.now();
+
+/**
+ * Appends an entry to the in-memory session log.
+ * @param {string} speaker
+ * @param {string} text
+ */
+function logMessage(speaker, text) {
+  sessionLog.push({ ts: Date.now(), speaker, text });
+}
+
+/**
+ * Formats the session log as Markdown and triggers a browser download.
+ */
+function exportSessionAsMarkdown() {
+  const startStr = new Date(sessionStart).toISOString().replace('T', ' ').slice(0, 19) + ' UTC';
+  const lines = [
+    '# Nexus Session Export',
+    '',
+    `**Session started:** ${startStr}`,
+    `**Messages:** ${sessionLog.length}`,
+    '',
+    '---',
+    '',
+  ];
+
+  for (const entry of sessionLog) {
+    const timeStr = new Date(entry.ts).toISOString().replace('T', ' ').slice(0, 19) + ' UTC';
+    lines.push(`### ${entry.speaker} — ${timeStr}`);
+    lines.push('');
+    lines.push(entry.text);
+    lines.push('');
+  }
+
+  if (sessionLog.length === 0) {
+    lines.push('*No messages recorded this session.*');
+    lines.push('');
+  }
+
+  const blob = new Blob([lines.join('\n')], { type: 'text/markdown' });
+  const url = URL.createObjectURL(blob);
+  const a = document.createElement('a');
+  a.href = url;
+  a.download = `nexus-session-${new Date(sessionStart).toISOString().slice(0, 10)}.md`;
+  a.click();
+  URL.revokeObjectURL(url);
+}
+
+const exportBtn = document.getElementById('export-session');
+if (exportBtn) {
+  exportBtn.addEventListener('click', exportSessionAsMarkdown);
+}
+
 window.addEventListener('chat-message', (/** @type {CustomEvent} */ event) => {
   console.log('Chat message:', event.detail);
   if (typeof event.detail?.text === 'string') {
+    logMessage(event.detail.speaker || 'TIMMY', event.detail.text);
     showTimmySpeech(event.detail.text);
     if (event.detail.text.toLowerCase().includes('sovereignty')) {
       triggerSovereigntyEasterEgg();