Set up project skeleton (milestone 1)

- Architecture and feature overview in docs/ARCHITECTURE.md
- Gradle 9.8 / AGP 9.4 / Kotlin 2.4 with version catalog and convention plugins
- Modules :app, :core:*, :device-profiles, :feature:* (placeholder screens)
- Flavors core (no INTERNET, enforced by a build check) and full
- Material You theme, navigation, expert mode and dry-run settings (DataStore)
- Pixel 8-10 device detection, unit tests, GPLv3 license, English README with Obtainium badge

Co-Authored-By: Claude Opus 5.5 <[email protected]>

core/data/build.gradle.kts

@@ -0,0 +1,14 @@
+plugins {
+    alias(libs.plugins.pixelwall.android.library)
+    alias(libs.plugins.pixelwall.android.hilt)
+}
+
+android {
+    namespace = "org.pixelwall.core.data"
+}
+
+dependencies {
+    api(project(":core:domain"))
+    implementation(libs.androidx.datastore.preferences)
+    implementation(libs.kotlinx.coroutines.android)
+}

core/data/src/main/kotlin/org/pixelwall/core/data/DataStoreUserPreferencesRepository.kt

@@ -0,0 +1,36 @@
+package org.pixelwall.core.data
+
+import androidx.datastore.core.DataStore
+import androidx.datastore.preferences.core.Preferences
+import androidx.datastore.preferences.core.booleanPreferencesKey
+import androidx.datastore.preferences.core.edit
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.map
+import org.pixelwall.core.domain.UserPreferences
+import org.pixelwall.core.domain.UserPreferencesRepository
+import javax.inject.Inject
+
+class DataStoreUserPreferencesRepository @Inject constructor(
+    private val dataStore: DataStore<Preferences>,
+) : UserPreferencesRepository {
+
+    override val preferences: Flow<UserPreferences> = dataStore.data.map { prefs ->
+        UserPreferences(
+            expertMode = prefs[EXPERT_MODE] ?: false,
+            dryRun = prefs[DRY_RUN] ?: false,
+        )
+    }
+
+    override suspend fun setExpertMode(enabled: Boolean) {
+        dataStore.edit { it[EXPERT_MODE] = enabled }
+    }
+
+    override suspend fun setDryRun(enabled: Boolean) {
+        dataStore.edit { it[DRY_RUN] = enabled }
+    }
+
+    private companion object {
+        val EXPERT_MODE = booleanPreferencesKey("expert_mode")
+        val DRY_RUN = booleanPreferencesKey("dry_run")
+    }
+}

core/data/src/main/kotlin/org/pixelwall/core/data/di/DataModule.kt

@@ -0,0 +1,31 @@
+package org.pixelwall.core.data.di
+
+import android.content.Context
+import androidx.datastore.core.DataStore
+import androidx.datastore.preferences.core.PreferenceDataStoreFactory
+import androidx.datastore.preferences.core.Preferences
+import androidx.datastore.preferences.preferencesDataStoreFile
+import dagger.Binds
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.android.qualifiers.ApplicationContext
+import dagger.hilt.components.SingletonComponent
+import org.pixelwall.core.data.DataStoreUserPreferencesRepository
+import org.pixelwall.core.domain.UserPreferencesRepository
+import javax.inject.Singleton
+
+@Module
+@InstallIn(SingletonComponent::class)
+abstract class DataModule {
+
+    @Binds
+    abstract fun bindUserPreferencesRepository(impl: DataStoreUserPreferencesRepository): UserPreferencesRepository
+
+    companion object {
+        @Provides
+        @Singleton
+        fun providePreferencesDataStore(@ApplicationContext context: Context): DataStore<Preferences> =
+            PreferenceDataStoreFactory.create { context.preferencesDataStoreFile("user_preferences") }
+    }
+}

core/data/src/test/kotlin/org/pixelwall/core/data/DataStoreUserPreferencesRepositoryTest.kt

@@ -0,0 +1,41 @@
+package org.pixelwall.core.data
+
+import androidx.datastore.preferences.core.PreferenceDataStoreFactory
+import com.google.common.truth.Truth.assertThat
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.test.TestScope
+import kotlinx.coroutines.test.UnconfinedTestDispatcher
+import kotlinx.coroutines.test.runTest
+import org.junit.Rule
+import org.junit.Test
+import org.junit.rules.TemporaryFolder
+import org.pixelwall.core.domain.UserPreferences
+
+@OptIn(ExperimentalCoroutinesApi::class)
+class DataStoreUserPreferencesRepositoryTest {
+
+    @get:Rule
+    val tmp = TemporaryFolder()
+
+    private val testScope = TestScope(UnconfinedTestDispatcher())
+
+    private fun repository() = DataStoreUserPreferencesRepository(
+        PreferenceDataStoreFactory.create(scope = testScope.backgroundScope) {
+            tmp.newFile("test.preferences_pb")
+        },
+    )
+
+    @Test
+    fun defaultsAreSafe() = testScope.runTest {
+        assertThat(repository().preferences.first()).isEqualTo(UserPreferences(expertMode = false, dryRun = false))
+    }
+
+    @Test
+    fun togglesArePersisted() = testScope.runTest {
+        val repo = repository()
+        repo.setExpertMode(true)
+        repo.setDryRun(true)
+        assertThat(repo.preferences.first()).isEqualTo(UserPreferences(expertMode = true, dryRun = true))
+    }
+}