ci(grinder): grinder を追加

1. `dart pub global activate grinder`
2. `dart pub add grinder`
3. `dart run grinder:init`

pubspec.lock

@@ -97,6 +97,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.3.1"
+  grinder:
+    dependency: "direct dev"
+    description:
+      name: grinder
+      sha256: e1996e485d2b56bb164a8585679758d488fbf567273f51c432c8733fee1f6188
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.9.5"
   http:
     dependency: transitive
     description:

pubspec.yaml

@@ -4,4 +4,5 @@ environment:
   sdk: ^3.3.1
 
 dev_dependencies:
+  grinder: ^0.9.5
   melos: ^6.0.0

tool/grind.dart

@@ -0,0 +1,17 @@
+// ignore_for_file: unreachable_from_main
+
+import 'package:grinder/grinder.dart';
+
+Future<void> main(List<String> args) async => grind(args);
+
+@Task()
+Future<dynamic> test() async => TestRunner().testAsync();
+
+@DefaultTask()
+@Depends(test)
+Future<void> build() async {
+  Pub.build();
+}
+
+@Task()
+void clean() => defaultClean();