Remove roots fallback suggestions for antigravity setup (#12941)

The latest version from 1/13 supports roots now

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Author: jakemac53

src/content/ai/mcp-server.md

@@ -95,26 +95,6 @@ From here, you can choose to install the MCP server from
 
 1.  In the list of available MCP servers,
     find or search for **Dart** and click **Install**.
-1.  **Important**: The built-in configuration doesn't currently pass the
-    required `--force-roots-fallback` flag. You must add it manually.
-1.  In the upper right of the **Manage MCPs** editor view,
-    click **View raw config**.
-1.  Locate the `dart-mcp-server` entry in the `mcpServers` map and
-    update its `args` list to include the `--force-roots-fallback` flag:
-
-    ```json title="mcp_config.json" highlightLines=7
-    {
-      "mcpServers": {
-        "dart-mcp-server": {
-          "command": "dart",
-          "args": [
-            "mcp-server",
-            "--force-roots-fallback"
-          ]
-        }
-      }
-    }
-    ```
 
 #### Connect manually {: #antigravity-mcp-manual-install}
 
@@ -128,8 +108,7 @@ From here, you can choose to install the MCP server from
         "dart-mcp-server": {
           "command": "dart",
           "args": [
-            "mcp-server",
-            "--force-roots-fallback"
+            "mcp-server"
           ],
           "env": {}
         }