feat: Reply/Zitat-Feature für Chat-Nachrichten

- Reply-Button (Hover) auf jeder User/Assistant-Nachricht
- Reply-Preview-Leiste über dem Input-Feld (mit Timestamp, Rolle, Text-Preview)
- Beim Senden: Zitat als Kontext-Block vorangestellt (> [Zitat: HH:MM, Role]:)
- User-Nachrichten parsen Zitat-Blöcke als visuelle Quote-Elemente (blaue Borderlinie)
- Timestamp-basierte Referenzierung (HH:MM oder DD.MM. HH:MM)
- clearReply() bei Chat-Clear, Navigation und Destroy

wwwroot/js/chat.js

@@ -32,6 +32,7 @@ const messages = [];
 let isStreaming = false;
 let pendingFiles = []; // [{ name, type, base64 }]
 let pendingRefs = [];  // [{ path, from, to }] - Workspace-Dateireferenzen
+let pendingReply = null; // { index, role, text } - Zitierte Nachricht
 let _lastDoneChainData = null; // Chain-Daten vom letzten done-Event
 let _chatAbandoned = false; // true wenn User weg-navigiert während Stream läuft
 
@@ -43,6 +44,7 @@ async function clearChat() {
   chatEl().innerHTML = '';
   lastKnownMessageId = 0;
   loadedArchiveCount = 0;
+  clearReply();
 
   setMeta(`Archiviert: ${archive.chainCount} Chains, ${archive.messageCount} Messages`);
   showArchiveLoadButton();
@@ -60,14 +62,24 @@ async function sendMessage() {
   let content;
   let bubbleText = text;
 
-  // Refs in den Text einbauen
+  // Reply-Zitat einbauen
   let msgText = text;
+  if (pendingReply) {
+    const roleLabel = pendingReply.role === 'user' ? 'User' : 'Assistant';
+    const timeLabel = _formatReplyTimestamp(pendingReply.timestamp);
+    const quoteText = pendingReply.text.split('\n').map(l => '> ' + l).join('\n');
+    const quoteHeader = `> [Zitat: ${timeLabel}, ${roleLabel}]:`;
+    msgText = quoteHeader + '\n' + quoteText + '\n\n' + (text || '');
+    clearReply();
+  }
+
+  // Refs in den Text einbauen
   if (pendingRefs.length > 0) {
     const refTags = pendingRefs.map(r => {
       if (r.from && r.to) return `[Datei: ${r.path}:${r.from}-${r.to}]`;
       return `[Datei: ${r.path}]`;
     });
-    msgText = refTags.join('\n') + (text ? '\n' + text : '');
+    msgText = refTags.join('\n') + (msgText ? '\n' + msgText : '');
     clearPendingRefs();
   }
 
@@ -324,3 +336,56 @@ function clearPendingFiles() {
   const fileInput = $('#fileInput');
   if (fileInput) fileInput.value = '';
 }
+
+// ── Reply / Quote ──
+
+function _formatReplyTimestamp(ts) {
+  if (!ts) return 'Jetzt';
+  try {
+    const d = new Date(ts);
+    const now = new Date();
+    const hh = d.getHours().toString().padStart(2, '0');
+    const mm = d.getMinutes().toString().padStart(2, '0');
+    // Gleiches Datum → nur Uhrzeit, sonst Datum + Uhrzeit
+    if (d.toDateString() === now.toDateString()) {
+      return hh + ':' + mm;
+    }
+    const dd = d.getDate().toString().padStart(2, '0');
+    const mo = (d.getMonth() + 1).toString().padStart(2, '0');
+    return dd + '.' + mo + '. ' + hh + ':' + mm;
+  } catch { return 'Jetzt'; }
+}
+
+function setReply(reply) {
+  pendingReply = reply;
+  renderReplyPreview();
+  document.getElementById('input')?.focus();
+}
+
+function clearReply() {
+  pendingReply = null;
+  renderReplyPreview();
+}
+
+function renderReplyPreview() {
+  const container = $('#replyPreview');
+  if (!container) return;
+
+  if (!pendingReply) {
+    container.innerHTML = '';
+    container.hidden = true;
+    return;
+  }
+
+  const roleLabel = pendingReply.role === 'user' ? 'User' : 'Assistant';
+  const timeLabel = _formatReplyTimestamp(pendingReply.timestamp);
+  const preview = truncate(pendingReply.text, 150);
+
+  container.innerHTML = `<div class="reply-preview-item">
+    <span class="reply-icon"><i class="fa fa-reply"></i></span>
+    <span class="reply-meta">${esc(timeLabel)}, ${esc(roleLabel)}</span>
+    <span class="reply-text">${esc(preview)}</span>
+    <button class="file-remove" onclick="clearReply()"><i class="fa fa-times"></i></button>
+  </div>`;
+  container.hidden = false;
+}