feat(settings): call the app "Clock" and add an app icon picker

The launcher and system label is now a plain, translatable "Clock"; the
brand name Clockula stays on the About card and in crash reports via an
untranslated app_brand_name string.

Settings → Appearance → App icon chooses between the bloom mark and a new
plain clock icon (the same dial and hands without the badge). The launcher
entry moves off MainActivity onto two <activity-alias> components, exactly
one enabled at a time, as Calendula does for its launcher name. The
component-enabled state is the single source of truth, and switching
enables the target before disabling the other so the launcher never sees
zero entries.

app/src/test/java/de/jeanlucmakiola/clockula/ManifestRulesTest.kt

@@ -31,7 +31,7 @@ class ManifestRulesTest {
     }
 
     @Test
-    fun `exactly the launcher, the door, the four widget configurators and the six widget receivers are exported`() {
+    fun `exactly the launcher and its two icon aliases, the door, the four widget configurators and the six widget receivers are exported`() {
         val exported = Regex("<(activity|service|receiver|provider)\\b[\\s\\S]*?(?:/>|</\\1>)")
             .findAll(text)
             .map { it.value }
@@ -49,6 +49,8 @@ class ManifestRulesTest {
         // widget configurators answer only APPWIDGET_CONFIGURE` below.
         assertThat(exported).containsExactly(
             ".MainActivity",
+            ".BloomIconAlias",
+            ".PlainIconAlias",
             ".interop.AlarmClockActivity",
             ".ui.widget.config.ClockWidgetConfigActivity",
             ".ui.widget.config.AnalogClockConfigActivity",
@@ -99,6 +101,27 @@ class ManifestRulesTest {
         assertThat(activityBlock(".MainActivity")).doesNotContain("android:permission")
     }
 
+    /**
+     * The launcher entry moved onto one alias per icon (LauncherIconManager).
+     * Exactly one may ship enabled, or a fresh install shows two icons or none.
+     */
+    @Test
+    fun `the launcher entry is two icon aliases, only the bloom enabled by default`() {
+        val aliases = Regex("<activity-alias\\b[\\s\\S]*?</activity-alias>").findAll(text)
+            .map { it.value }
+            .associateBy { Regex("android:name=\"([^\"]+)\"").find(it)!!.groupValues[1] }
+
+        assertThat(aliases.keys).containsExactly(".BloomIconAlias", ".PlainIconAlias")
+        for (block in aliases.values) {
+            assertThat(block).contains("android:targetActivity=\".MainActivity\"")
+            assertThat(block).contains("android.intent.category.LAUNCHER")
+            assertThat(block).doesNotContain("android:permission")
+        }
+        assertThat(aliases.getValue(".BloomIconAlias")).contains("android:enabled=\"true\"")
+        assertThat(aliases.getValue(".PlainIconAlias")).contains("android:enabled=\"false\"")
+        assertThat(activityBlock(".MainActivity")).doesNotContain("android.intent.category.LAUNCHER")
+    }
+
     @Test
     fun `every action the contract answers is named in the manifest`() {
         val missing = AlarmClockContract.ACTIONS.filterNot { text.contains("android:name=\"$it\"") }

app/src/test/java/de/jeanlucmakiola/clockula/data/appicon/LauncherIconManagerTest.kt

@@ -0,0 +1,39 @@
+package de.jeanlucmakiola.clockula.data.appicon
+
+import android.content.pm.PackageManager
+import com.google.common.truth.Truth.assertThat
+import org.junit.jupiter.api.Test
+
+/**
+ * The pure decision logic behind the app-icon picker. The `PackageManager`
+ * seam itself is exercised on-device; these pin the read interpretation and
+ * the write order.
+ */
+class LauncherIconManagerTest {
+
+    @Test
+    fun `an enabled plain alias reads as PLAIN`() {
+        assertThat(launcherIconFor(PackageManager.COMPONENT_ENABLED_STATE_ENABLED))
+            .isEqualTo(LauncherIcon.PLAIN)
+    }
+
+    @Test
+    fun `a default or disabled plain alias reads as BLOOM`() {
+        assertThat(launcherIconFor(PackageManager.COMPONENT_ENABLED_STATE_DEFAULT))
+            .isEqualTo(LauncherIcon.BLOOM)
+        assertThat(launcherIconFor(PackageManager.COMPONENT_ENABLED_STATE_DISABLED))
+            .isEqualTo(LauncherIcon.BLOOM)
+    }
+
+    @Test
+    fun `the write plan enables the target before disabling the other`() {
+        assertThat(iconWritePlan(LauncherIcon.PLAIN)).containsExactly(
+            IconAliasChange(LauncherIcon.PLAIN, enabled = true),
+            IconAliasChange(LauncherIcon.BLOOM, enabled = false),
+        ).inOrder()
+        assertThat(iconWritePlan(LauncherIcon.BLOOM)).containsExactly(
+            IconAliasChange(LauncherIcon.BLOOM, enabled = true),
+            IconAliasChange(LauncherIcon.PLAIN, enabled = false),
+        ).inOrder()
+    }
+}

app/src/test/java/de/jeanlucmakiola/clockula/testing/FakeLauncherIconManager.kt

@@ -0,0 +1,13 @@
+package de.jeanlucmakiola.clockula.testing
+
+import de.jeanlucmakiola.clockula.data.appicon.LauncherIcon
+import de.jeanlucmakiola.clockula.data.appicon.LauncherIconManager
+
+/** The launcher icon as a plain field, starting at the manifest default. */
+class FakeLauncherIconManager(var icon: LauncherIcon = LauncherIcon.BLOOM) : LauncherIconManager {
+    override fun current(): LauncherIcon = icon
+
+    override fun set(icon: LauncherIcon) {
+        this.icon = icon
+    }
+}

app/src/test/java/de/jeanlucmakiola/clockula/ui/settings/SettingsViewModelTest.kt

@@ -1,8 +1,10 @@
 package de.jeanlucmakiola.clockula.ui.settings
 
 import com.google.common.truth.Truth.assertThat
+import de.jeanlucmakiola.clockula.data.appicon.LauncherIcon
 import de.jeanlucmakiola.clockula.domain.DismissChallenge
 import de.jeanlucmakiola.clockula.testing.FakeDeviceStateReader
+import de.jeanlucmakiola.clockula.testing.FakeLauncherIconManager
 import de.jeanlucmakiola.clockula.testing.FakeRingtoneCatalog
 import de.jeanlucmakiola.clockula.testing.FakeRingtonePreviewer
 import de.jeanlucmakiola.clockula.testing.MainDispatcherExtension
@@ -34,7 +36,10 @@ class SettingsViewModelTest {
     @RegisterExtension
     val main = MainDispatcherExtension()
 
-    private fun TestScope.newViewModel(tempDir: Path): SettingsViewModel {
+    private fun TestScope.newViewModel(
+        tempDir: Path,
+        launcherIcons: FakeLauncherIconManager = FakeLauncherIconManager(),
+    ): SettingsViewModel {
         val harness = worldClockHarness(tempDir)
         return SettingsViewModel(
             settings = harness.settings,
@@ -42,6 +47,8 @@ class SettingsViewModelTest {
             preview = FakeRingtonePreviewer(),
             worldClocks = harness.source,
             deviceState = FakeDeviceStateReader(),
+            launcherIcons = launcherIcons,
+            io = main.dispatcher,
         )
     }
 
@@ -65,6 +72,21 @@ class SettingsViewModelTest {
         assertThat(loaded.defaults.snoozeMinutes).isEqualTo(10)
     }
 
+    @Test
+    fun `the launcher icon reads the component state and writes through`(@TempDir tempDir: Path) =
+        runTest(main.dispatcher) {
+            val icons = FakeLauncherIconManager(LauncherIcon.PLAIN)
+            val viewModel = newViewModel(tempDir, icons)
+            advanceUntilIdle()
+            assertThat(viewModel.launcherIcon.value).isEqualTo(LauncherIcon.PLAIN)
+
+            viewModel.onLauncherIconSelected(LauncherIcon.BLOOM)
+            advanceUntilIdle()
+
+            assertThat(icons.icon).isEqualTo(LauncherIcon.BLOOM)
+            assertThat(viewModel.launcherIcon.value).isEqualTo(LauncherIcon.BLOOM)
+        }
+
     @Test
     fun `the theme mode writes through`(@TempDir tempDir: Path) = runTest(main.dispatcher) {
         val viewModel = collecting(newViewModel(tempDir))