feat(j0.1): squelette projet Flutter + arborescence clean archi

- flutter create --platforms=android --org biz.siteop
- arborescence lib/core/{error,theme,router,di} et lib/features/{locking,playback,podcasts,parental,limits}/{domain,application,data,presentation}
- pubspec.yaml : flutter_riverpod ^2.6.1 (YAGNI — autres paquets aux jalons suivants)
- lib/main.dart : ProviderScope + StorytimeApp (MaterialApp + écran placeholder)
- test/app_boots_test.dart : TDD Red→Green vérifié (flutter test vert, flutter analyze 0 issue)
- README.md : prérequis Flutter 3.41.6 / Dart 3.11.4

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

android/app/build.gradle.kts

@@ -0,0 +1,44 @@
+plugins {
+    id("com.android.application")
+    id("kotlin-android")
+    // The Flutter Gradle Plugin must be applied after the Android and Kotlin Gradle plugins.
+    id("dev.flutter.flutter-gradle-plugin")
+}
+
+android {
+    namespace = "biz.siteop.storytime"
+    compileSdk = flutter.compileSdkVersion
+    ndkVersion = flutter.ndkVersion
+
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_17
+        targetCompatibility = JavaVersion.VERSION_17
+    }
+
+    kotlinOptions {
+        jvmTarget = JavaVersion.VERSION_17.toString()
+    }
+
+    defaultConfig {
+        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
+        applicationId = "biz.siteop.storytime"
+        // You can update the following values to match your application needs.
+        // For more information, see: https://flutter.dev/to/review-gradle-config.
+        minSdk = flutter.minSdkVersion
+        targetSdk = flutter.targetSdkVersion
+        versionCode = flutter.versionCode
+        versionName = flutter.versionName
+    }
+
+    buildTypes {
+        release {
+            // TODO: Add your own signing config for the release build.
+            // Signing with the debug keys for now, so `flutter run --release` works.
+            signingConfig = signingConfigs.getByName("debug")
+        }
+    }
+}
+
+flutter {
+    source = "../.."
+}