Bump ai to 61ba1ea081dbc83c89b62bd65336328a71fda858

Changes:
```
> git log --format="%C(auto) %h %s" 64dfa7f..61ba1ea
 https://dart.googlesource.com/ai.git/+/61ba1ea Add more and better examples (228)
 https://dart.googlesource.com/ai.git/+/b77cda5 add a CI check that the readme file is up-to-date (192)
 https://dart.googlesource.com/ai.git/+/9c62524 Allow multiple package arguments to pub commands (226)
 https://dart.googlesource.com/ai.git/+/c1a1027 Started omitting instructions if they are null. (221)
 https://dart.googlesource.com/ai.git/+/9b007b3 Add failure reasons to tool call analytics events (219)
 https://dart.googlesource.com/ai.git/+/c8dc5da don't bail early when running in multiple roots (218)
 https://dart.googlesource.com/ai.git/+/2541b6c Remove VS Code mcp instructions in favor of Dart-Code setting. (206)
 https://dart.googlesource.com/ai.git/+/70daa1f release dart_mcp 0.3.0 (216)
 https://dart.googlesource.com/ai.git/+/a252a46 add retry logic to try and make dtd_test less flaky (214)
 https://dart.googlesource.com/ai.git/+/9e0b973 add a test that the arg parser library only depends on package:args (213)

```

Diff: https://dart.googlesource.com/ai.git/+/64dfa7f138aa4d9bcc06e807858136b7d4d296d3..61ba1ea081dbc83c89b62bd65336328a71fda858/
Change-Id: Ib63da49ddd084d89b0b9d9d664a7284c20e08f59
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/440684
Reviewed-by: Jake Macdonald <[email protected]>
Commit-Queue: Devon Carew <[email protected]>

Author: devoncarew

DEPS

@@ -131,7 +131,7 @@ vars = {
   ### /third_party/pkg dependencies
   # 'tools/rev_sdk_deps.dart' will rev pkg dependencies to their latest; put an
   # EOL comment after a dependency to instead pin at the current revision.
-  "ai_rev": "64dfa7f138aa4d9bcc06e807858136b7d4d296d3",
+  "ai_rev": "61ba1ea081dbc83c89b62bd65336328a71fda858",
   "core_rev": "b59ecf4ceebe6153e1c0166b7c9a7fdd9458a89d",
   "dartdoc_rev": "882aea9351262d618c955322f4c9aafe9540b848",
   "ecosystem_rev": "d5233c6dd0767cffa5742e32c4bc7c230c9c4b12",

pkg/dartdev/test/commands/mcp_server_test.dart

@@ -5,6 +5,7 @@
 import 'dart:io';
 
 import 'package:dart_mcp/client.dart';
+import 'package:dart_mcp/stdio.dart';
 import 'package:test/test.dart';
 
 void main() {
@@ -19,23 +20,25 @@ void main() {
           'mcp-server',
           if (withExperiment) '--experimental-mcp-server',
         ]);
-        final serverConnection = client.connectStdioServer(
-            process.stdin, process.stdout,
-            onDone: process.kill);
-        final initializeResult = await serverConnection.initialize(
-            InitializeRequest(
-                protocolVersion: ProtocolVersion.latestSupported,
-                capabilities: client.capabilities,
-                clientInfo: client.implementation));
+
+        final connection = client.connectServer(
+          stdioChannel(input: process.stdout, output: process.stdin),
+        );
+        connection.done.then((_) => process.kill());
+
+        final initializeResult = await connection.initialize(
+          InitializeRequest(
+            protocolVersion: ProtocolVersion.latestSupported,
+            capabilities: client.capabilities,
+            clientInfo: client.implementation,
+          ),
+        );
 
         expect(
             initializeResult.protocolVersion, ProtocolVersion.latestSupported);
-        serverConnection.notifyInitialized();
+        connection.notifyInitialized();
 
-        expect(
-          await serverConnection.listTools(ListToolsRequest()),
-          isNotEmpty,
-        );
+        expect(await connection.listTools(ListToolsRequest()), isNotEmpty);
       });
     }
   });