fix(mcp): respect configured package registry

Closes #5912

apps/desktop/src/components/editor/EditorSettingsDialog.vue

@@ -1816,7 +1816,7 @@ const mcpStatusLabel = computed(() => {
 });
 
 const mcpCommand = computed(() => {
-  if (!mcpStatus.value) return "npm install -g @dbx-app/mcp-server@latest --registry=https://registry.npmjs.org";
+  if (!mcpStatus.value) return "npm install -g @dbx-app/mcp-server@latest";
   return mcpStatus.value.installed ? mcpStatus.value.update_command : mcpStatus.value.install_command;
 });
 

apps/desktop/src/lib/backend/http.ts

@@ -3787,8 +3787,8 @@ export async function checkMcpServerStatus(): Promise<import("@/lib/backend/taur
     native_bin_path: null,
     script_path: null,
     data_dir: null,
-    install_command: "npm install -g @dbx-app/mcp-server@latest --registry=https://registry.npmjs.org",
-    update_command: "npm install -g @dbx-app/mcp-server@latest --registry=https://registry.npmjs.org",
+    install_command: "npm install -g @dbx-app/mcp-server@latest",
+    update_command: "npm install -g @dbx-app/mcp-server@latest",
     error: "MCP Server status is only available in the desktop app.",
   };
 }