Implemented the Persisting the selected locale across launches on the ContentView view in the Sample app target.

Apps/Attendi/Tests/Attendi.xctestplan

@@ -0,0 +1,24 @@
+{
+  "configurations" : [
+    {
+      "id" : "D599315E-CE89-41A2-A181-811F9CF40731",
+      "name" : "Configuration 1",
+      "options" : {
+
+      }
+    }
+  ],
+  "defaultOptions" : {
+
+  },
+  "testTargets" : [
+    {
+      "target" : {
+        "containerPath" : "container:Attendi.xcodeproj",
+        "identifier" : "0296F7992FFA954E00D2C5FC",
+        "name" : "AttendiTests"
+      }
+    }
+  ],
+  "version" : 1
+}

Apps/Attendi/Tests/View Models/ContentViewModelTests.swift

@@ -25,7 +25,7 @@ struct ContentViewModelTests {
 
             let model = Model(preinstaller: preinstaller)
 
-            await model.load()
+            await model.load(identifier: "")
 
             #expect(model.locale == .english)
             #expect(model.locales.count == 2)
@@ -33,6 +33,34 @@ struct ContentViewModelTests {
             #expect(model.locales.contains(.english))
         }
 
+        @Test
+        func `load restores the persisted locale`() async {
+            let preinstaller = PreinstallingMock()
+
+            preinstaller.localesSupported = [.dutch, .english]
+            preinstaller.equivalents = [.dutch: .dutch]
+
+            let model = Model(preinstaller: preinstaller)
+
+            await model.load(identifier: Locale.dutch.identifier)
+
+            #expect(model.locale == .dutch)
+        }
+
+        @Test
+        func `load falls back to the default locale when the persisted locale is unsupported`() async {
+            let preinstaller = PreinstallingMock()
+
+            preinstaller.localesSupported = [.dutch, .english]
+            preinstaller.equivalents = [.byDefault: .english]
+
+            let model = Model(preinstaller: preinstaller)
+
+            await model.load(identifier: "fr-FR")
+
+            #expect(model.locale == .english)
+        }
+
         @Test
         func `load preinstalls the aligned locale`() async throws {
             let preinstaller = PreinstallingMock()
@@ -42,7 +70,7 @@ struct ContentViewModelTests {
 
             let model = Model(preinstaller: preinstaller)
 
-            await model.load()
+            await model.load(identifier: "")
 
             try await Task.sleep(for: .seconds(0.1))
 
@@ -203,6 +231,8 @@ struct ContentViewModelTests {
 // MARK: - Constants
 
 private extension Locale {
+    /// The locale the model falls back to when no equivalent of the current locale is supported.
+    static let byDefault = Locale(identifier: "en_US")
     /// A supported locale to preinstall in the tests.
     static let dutch = Locale(identifier: "nl-NL")
     /// Another supported locale to preinstall in the tests.