refactor: extract conflict panel host mount helper

rust/crates/mnote-web/browser/document-conflict-panel-runtime.js

@@ -17,12 +17,29 @@ function clearSessionConflictSurface(session, deps) {
     ? deps.sessionViews(session)
     : [];
   views.forEach(function(view) {
-    var host = view.runtimeDescriptor.root.closest('.document-pane') || view.runtimeDescriptor.root;
+    var host = conflictPanelHost(view && view.runtimeDescriptor && view.runtimeDescriptor.root);
     if (!(host instanceof HTMLElement)) return;
     host.querySelectorAll('[data-testid="mnote-editor-conflict-panel"]').forEach(function(node) { node.remove(); });
   });
 }
 
+function conflictPanelHost(root) {
+  if (!(root instanceof Element)) return null;
+  return root.closest('.document-pane') || root;
+}
+
+function mountSessionConflictPanel(root, panel) {
+  var host = conflictPanelHost(root);
+  if (!(host instanceof HTMLElement) || !(panel instanceof HTMLElement)) return false;
+  var header = host.querySelector('.document-shell-header');
+  if (header && header.parentNode) {
+    header.parentNode.insertBefore(panel, header.nextSibling);
+  } else {
+    host.prepend(panel);
+  }
+  return true;
+}
+
 function createSessionConflictPanel(session, message, deps) {
   deps = deps || {};
   var externalConflictMessage = String(deps.externalConflictMessage || '').trim() || '文件已在外部修改';
@@ -185,6 +202,7 @@ function runSessionConflictAction(action, deps) {
 window.__mnoteDocumentConflictPanelRuntime = {
   clearSessionConflictSurface: clearSessionConflictSurface,
   createSessionConflictPanel: createSessionConflictPanel,
+  mountSessionConflictPanel: mountSessionConflictPanel,
   populateSessionConflictDiffPanel: populateSessionConflictDiffPanel,
   runSessionConflictAction: runSessionConflictAction
 };