feat: Web-Search Sources anzeigen (Streaming + History + Archive + Shared)

Backend:
- web_search_tool_result Sources extrahieren (url, title)
- Als 'web_search_result' Message-Typ in DB persistieren
- Sources im web_search_end SSE-Event mitsenden
- Alle 3 Chat-Pfade: StreamChat, RunAgentChat, ChatNonStreaming

Frontend:
- renderToolBoxContent: Sources-Sektion mit klickbaren Domain-Links
- finishToolBox/addToolBoxStatic: sources-Parameter durchgereicht
- History: web_search_result Message-Typ in allen 3 Render-Pfaden
- web_search immer sichtbar (auch bei 'modifications' Filter)

CSS:
- .web-search-sources: Flex-Wrap Container
- .web-search-source: Domain-Pill mit Hover-Effekt, Title-Ellipsis

wwwroot/js/ui.js

@@ -823,7 +823,8 @@ function isToolVisible(toolName) {
   const mode = loadSettings().toolCallDisplay;
   if (mode === 'all') return true;
   if (mode === 'hidden') return false;
-  // 'modifications' – nur modifizierende Tools anzeigen
+  // 'modifications' – nur modifizierende Tools + web_search anzeigen
+  if (toolName === 'web_search') return true;
   return MODIFICATION_TOOLS.includes(toolName);
 }
 
@@ -855,7 +856,7 @@ function addToolBoxLoading(name) {
   return div;
 }
 
-function renderToolBoxContent(div, name, inputJson, result, isError) {
+function renderToolBoxContent(div, name, inputJson, result, isError, sources) {
   let parsedInput = null;
   try { parsedInput = JSON.parse(inputJson); } catch {}
 
@@ -879,6 +880,25 @@ function renderToolBoxContent(div, name, inputJson, result, isError) {
 
   let foldTarget = null;
 
+  // Web-Search Sources – immer sichtbar, kein Toggle
+  if (name === 'web_search' && sources && sources.length > 0) {
+    const sourcesList = document.createElement('div');
+    sourcesList.className = 'web-search-sources';
+    sources.forEach(function(s) {
+      const link = document.createElement('a');
+      link.href = s.url;
+      link.target = '_blank';
+      link.rel = 'noopener noreferrer';
+      link.className = 'web-search-source';
+      var domain = '';
+      try { domain = new URL(s.url).hostname.replace('www.', ''); } catch(e) { domain = s.url; }
+      link.innerHTML = '<i class="fa fa-external-link"></i> <span class="source-domain">' + esc(domain) + '</span>' +
+        (s.title ? '<span class="source-title">' + esc(s.title) + '</span>' : '');
+      sourcesList.appendChild(link);
+    });
+    div.appendChild(sourcesList);
+  }
+
   if (name === 'edit_file' && parsedInput && parsedInput.path) {
     const pathSpan = document.createElement('span');
     pathSpan.className = 'tool-input';
@@ -1072,15 +1092,15 @@ function buildTodoList(result, isError) {
 
 function finishToolBox(div, data) {
   if (!div) return;
-  renderToolBoxContent(div, data.name, data.input, data.result, data.isError);
+  renderToolBoxContent(div, data.name, data.input, data.result, data.isError, data.sources);
   scrollDown();
 }
 
-function addToolBoxStatic(name, input, result, isError) {
+function addToolBoxStatic(name, input, result, isError, sources) {
   const div = document.createElement('div');
   div.className = 'tool-box';
   div.dataset.toolName = name;
-  renderToolBoxContent(div, name, input, result, isError);
+  renderToolBoxContent(div, name, input, result, isError, sources);
   chatEl().appendChild(div);
   scrollDown();
 }