feat: chat improvements, file viewer, usage fixes, and agent filesystem awareness

server/web/templates/files.html

@@ -42,7 +42,7 @@
           <th>Name</th>
           <th style="width:100px;text-align:right">Size</th>
           <th style="width:170px">Modified</th>
-          <th style="width:140px"></th>
+          <th style="width:180px"></th>
         </tr>
       </thead>
       <tbody id="file-tbody">
@@ -58,4 +58,20 @@
 
 </div>
 
+<!-- File viewer modal -->
+<div class="modal-overlay" id="file-viewer-modal" style="display:none;align-items:flex-start;padding:40px 16px"
+     onclick="if(event.target===this)closeFileViewer()">
+  <div class="modal" style="max-width:860px;width:100%;max-height:calc(100vh - 80px);display:flex;flex-direction:column">
+    <div class="modal-header" style="display:flex;align-items:center;justify-content:space-between;margin-bottom:12px">
+      <span id="fv-title" style="font-family:var(--mono);font-size:13px;color:var(--text-dim);overflow:hidden;text-overflow:ellipsis;white-space:nowrap;max-width:calc(100% - 40px)"></span>
+      <button class="btn btn-ghost btn-small" onclick="closeFileViewer()">✕</button>
+    </div>
+    <div id="fv-truncated" style="display:none;font-size:12px;color:var(--yellow);margin-bottom:8px"></div>
+    <pre id="fv-content"
+         style="margin:0;overflow:auto;flex:1;background:var(--bg3);border:1px solid var(--border);
+                border-radius:4px;padding:12px 14px;font-family:var(--mono);font-size:12px;
+                line-height:1.6;white-space:pre-wrap;word-break:break-all;max-height:70vh"></pre>
+  </div>
+</div>
+
 {% endblock %}