test(arch): keep the alarm engine free of Android

The engine and the domain stay plain Kotlin, which is the only reason the
DST, skip and snooze behaviour can be pinned by 326 JVM tests instead of an
emulator. That is worth a test that fails the build when it stops being true.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

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

@@ -46,6 +46,9 @@ class ArchitectureRulesTest {
             "TimerEntity",
             "WorldClockEntity",
             "LapEntity",
+            "AlarmStateEntity",
+            "AlarmStateDao",
+            "AlarmStateMapper",
             "AlarmDao",
             "TimerDao",
             "WorldClockDao",
@@ -66,4 +69,21 @@ class ArchitectureRulesTest {
 
         assertThat(offenders).isEmpty()
     }
+
+    @Test
+    fun `the alarm engine and its pure neighbours stay free of Android types`() {
+        val jvmTestable = kotlinSources.filter { file ->
+            val path = file.invariantSeparatorsPath
+            path.contains("de/jeanlucmakiola/clockula/domain/alarm/") ||
+                path.endsWith("de/jeanlucmakiola/clockula/alarm/AlarmEngine.kt") ||
+                path.endsWith("de/jeanlucmakiola/clockula/alarm/AlarmResolver.kt") ||
+                path.contains("de/jeanlucmakiola/clockula/system/")
+        }
+
+        val offenders = jvmTestable.filter { file ->
+            file.readLines().any { it.startsWith("import android.") || it.startsWith("import androidx.") }
+        }.map { it.invariantSeparatorsPath }
+
+        assertThat(offenders).isEmpty()
+    }
 }