refactor: ui.js, chat.js, history.js in 13 modulare Dateien aufteilen

Die monolithische ui.js (1534 Zeilen) zusammen mit chat.js (612) und
history.js (626) in fokussierte Module aufgeteilt:

Neue Dateien aus ui.js:
- ui-helpers.js (126) - DOM-Utilities, $, esc, truncate, scrollDown, Toast
- markdown.js (143) - renderMarkdown, wrapKreaGalleries, LaTeX/Code-Schutz
- cards.js (90) - buildSessionCard, buildAgentCard
- msg-actions.js (208) - Delete, Mark, Share, Reply-Button, Timestamp
- tool-ui.js (332) - Tool-Boxes, Diffs, Todo-Liste, Visibility
- modals.js (190) - System-Prompt, Command-Output, Krea-Image Modals
- stream-ui.js (124) - Stream-Bubble, Review-Streaming
- bubbles.js (312) - User/Assistant/Error/Warning/Choice/Review Bubbles

Neue Dateien aus chat.js:
- reply.js (54) - Reply/Quote-Handling mit pendingReply State
- files.js (110) - File-Upload, Workspace-Refs mit pendingFiles/Refs State

Neue Datei aus history.js:
- archive.js (173) - Archiv-Loading mit loadedArchiveCount State

Verbleibend:
- chat.js (448) - Stream-Events, sendMessage, handleChoiceClick, Plan-Mode
- history.js (464) - History laden, Polling, Message-Rendering

Kein Code verändert, nur verschoben. Alle 94 Funktionen verifiziert.
Globale Variablen in die Module verschoben, wo sie primär genutzt werden.

wwwroot/js/stream-ui.js

@@ -0,0 +1,124 @@
+// ── Streaming Bubble ──
+
+let _streamDiv = null;
+let _streamText = '';
+
+function startStreamBubble() {
+  _streamDiv = document.createElement('div');
+  _streamDiv.className = 'msg assistant markdown streamed';
+  _streamDiv.innerHTML = '<p><span class="cursor"></span></p>';
+  _streamText = '';
+  chatEl().appendChild(_streamDiv);
+  scrollDown();
+}
+
+function appendToStream(text) {
+  if (!_streamDiv) startStreamBubble();
+  _streamText += text;
+  _streamDiv.innerHTML = renderMarkdown(_streamText);
+  // Cursor ins letzte Inline/Text-Element einfügen, damit er nicht auf eine neue Zeile rutscht
+  const cursor = document.createElement('span');
+  cursor.className = 'cursor';
+  const lastBlock = _streamDiv.lastElementChild;
+  if (lastBlock) {
+    lastBlock.appendChild(cursor);
+  } else {
+    _streamDiv.appendChild(cursor);
+  }
+  scrollDown();
+}
+
+function pauseStreamBubble() {
+  // Cursor entfernen, aber Bubble + Text behalten (z.B. bei Web-Search-Pause)
+  if (_streamDiv) {
+    const cursor = _streamDiv.querySelector('.cursor');
+    if (cursor) cursor.remove();
+  }
+}
+
+function endStreamBubble() {
+  if (_streamDiv) {
+    const cursor = _streamDiv.querySelector('.cursor');
+    if (cursor) cursor.remove();
+    if (!_streamText.trim()) _streamDiv.remove();
+    else {
+      _streamDiv.innerHTML = renderMarkdown(_streamText);
+      parseFluentEmojis(_streamDiv);
+      wrapKreaGalleries(_streamDiv);
+    }
+  }
+  _streamDiv = null;
+  _streamText = '';
+}
+
+// ── Review Bubbles (Streaming) ──
+
+let _reviewBubble = null;
+let _reviewTextEl = null;
+let _reviewText = '';
+
+function addReviewBubble(type, data, agentType) {
+  _reviewBubble = document.createElement('div');
+  _reviewBubble.className = 'msg review-bubble streamed';
+  if (agentType === 'finalizer') _reviewBubble.classList.add('finalizer-bubble');
+  if (agentType === 'preparer') _reviewBubble.classList.add('preparer-bubble');
+  const header = document.createElement('div');
+  header.className = 'review-header';
+  if (agentType === 'preparer') {
+    header.innerHTML = '<i class="fa fa-filter"></i> <strong>' + esc(data.agentName || 'Vorbereiter-Agent') + '</strong>';
+  } else if (agentType === 'finalizer') {
+    header.innerHTML = '<i class="fa fa-flag-checkered"></i> <strong>' + esc(data.agentName || 'Finalizer-Agent') + '</strong>';
+  } else {
+    header.innerHTML = '<i class="fa fa-check-circle-o"></i> <strong>' + esc(data.agentName || 'Review-Agent') + '</strong> <span class="review-round">Runde ' + data.round + '/' + data.maxRounds + '</span>';
+  }
+  _reviewBubble.appendChild(header);
+  _reviewTextEl = document.createElement('div');
+  _reviewTextEl.className = 'review-content markdown';
+  _reviewBubble.appendChild(_reviewTextEl);
+  _reviewText = '';
+  chatEl().appendChild(_reviewBubble);
+  scrollDown();
+}
+
+function appendToReviewText(text) {
+  if (!_reviewBubble) return;
+  _reviewText += text;
+  _reviewTextEl.innerHTML = renderMarkdown(_reviewText);
+  scrollDown();
+}
+
+function addReviewToolUse(data) {
+  if (!_reviewBubble) return;
+  const toolDiv = document.createElement('div');
+  toolDiv.className = 'review-tool-use';
+  toolDiv.innerHTML = '<i class="fa fa-wrench"></i> <span class="tool-name">' + esc(data.toolName) + '</span>';
+  _reviewBubble.appendChild(toolDiv);
+  scrollDown();
+}
+
+function finalizeReviewBubble(type, data, agentType) {
+  if (!_reviewBubble) return;
+  const status = document.createElement('div');
+  status.className = 'review-status';
+  if (agentType === 'preparer' && type === 'forwarded') {
+    status.className += ' review-approved';
+    status.innerHTML = '<i class="fa fa-arrow-right"></i> Weitergeleitet an Session-Agent';
+  } else if (agentType === 'preparer' && type === 'query') {
+    status.className += ' review-rejected';
+    status.innerHTML = '<i class="fa fa-question-circle"></i> Rückfrage an User';
+  } else if (agentType === 'finalizer' || type === 'done') {
+    status.className += ' review-approved';
+    status.innerHTML = '<i class="fa fa-flag-checkered"></i> Abgeschlossen';
+  } else if (type === 'approved') {
+    status.className += ' review-approved';
+    status.innerHTML = '<i class="fa fa-check"></i> Approved';
+  } else {
+    status.className += ' review-rejected';
+    status.innerHTML = '<i class="fa fa-repeat"></i> Feedback – Worker korrigiert...';
+  }
+  _reviewBubble.appendChild(status);
+  _reviewBubble = null;
+  _reviewTextEl = null;
+  _reviewText = '';
+  scrollDown();
+}