Formatted the boilerplated code in the app as well as the unit and UI tests targets.

App/Sources/App/TodosApp.swift

@@ -1,17 +1,18 @@
-import SwiftUI
 import SwiftData
+import SwiftUI
 
 @main
 struct TodosApp: App {
     var sharedModelContainer: ModelContainer = {
         let schema = Schema([
-            Item.self,
+            Item.self
         ])
         let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false)
 
         do {
             return try ModelContainer(for: schema, configurations: [modelConfiguration])
-        } catch {
+        }
+        catch {
             fatalError("Could not create ModelContainer: \(error)")
         }
     }()

App/Sources/Views/ContentView.swift

@@ -1,9 +1,13 @@
-import SwiftUI
 import SwiftData
+import SwiftUI
 
 struct ContentView: View {
-    @Environment(\.modelContext) private var modelContext
+
-    @Query private var items: [Item]
+    @Environment(\.modelContext)
+    private var modelContext
+
+    @Query
+    private var items: [Item]
 
     var body: some View {
         NavigationSplitView {
@@ -17,15 +21,15 @@ struct ContentView: View {
                 }
                 .onDelete(perform: deleteItems)
             }
-#if os(macOS)
+            #if os(macOS)
             .navigationSplitViewColumnWidth(min: 180, ideal: 200)
-#endif
+            #endif
             .toolbar {
-#if os(iOS)
+                #if os(iOS)
                 ToolbarItem(placement: .navigationBarTrailing) {
                     EditButton()
                 }
-#endif
+                #endif
                 ToolbarItem {
                     Button(action: addItem) {
                         Label("Add Item", systemImage: "plus")

UITests/TodosUITestsLaunchTests.swift

@@ -23,5 +23,5 @@ final class TodosUITestsLaunchTests: XCTestCase {
         attachment.lifetime = .keepAlways
         add(attachment)
     }
-}
 
+}

UnitTests/TodosTests.swift

@@ -2,8 +2,8 @@ import Testing
 
 struct TodosTests {
 
-    @Test func example() async throws {
+    @Test
+    func example() async throws {
         // Write your test here and use APIs like `#expect(...)` to check expected conditions.
     }
-
 }