fix(lifecycle): preserve connection across activity recreation

app/src/test/java/com/m57/hermescontrol/MainActivityLifecycleTest.kt

@@ -0,0 +1,75 @@
+package com.m57.hermescontrol
+
+import com.m57.hermescontrol.notification.NotificationHelper
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.mockkObject
+import io.mockk.unmockkAll
+import io.mockk.verify
+import org.junit.After
+import org.junit.Test
+import java.lang.reflect.InvocationTargetException
+
+class MainActivityLifecycleTest {
+    @After
+    fun tearDown() {
+        unmockkAll()
+        ExternalActivityLifecycleGuard.resetForTest()
+    }
+
+    @Test
+    fun `pause prepares notifications without declaring the app backgrounded`() {
+        mockkObject(NotificationHelper)
+        every { NotificationHelper.start(any()) } returns Unit
+        every { NotificationHelper.setAppForeground(any(), any()) } returns Unit
+        val activity = mockk<MainActivity>(relaxed = true)
+        every { activity invoke "onPause" withArguments emptyList() } answers { callOriginal() }
+
+        invokeLifecycle(activity, "onPause")
+
+        verify(exactly = 1) { NotificationHelper.start(activity) }
+        verify(exactly = 0) { NotificationHelper.setAppForeground(activity, false) }
+    }
+
+    @Test
+    fun `configuration stop keeps the shared connection foregrounded`() {
+        mockkObject(NotificationHelper)
+        every { NotificationHelper.setAppForeground(any(), any()) } returns Unit
+        val activity = mockk<MainActivity>(relaxed = true)
+        every { activity.isChangingConfigurations } returns true
+        every { activity invoke "onStop" withArguments emptyList() } answers { callOriginal() }
+
+        invokeLifecycle(activity, "onStop")
+
+        verify(exactly = 0) { NotificationHelper.setAppForeground(activity, false) }
+    }
+
+    @Test
+    fun `real background stop still enables idle socket cleanup`() {
+        mockkObject(NotificationHelper)
+        every { NotificationHelper.setAppForeground(any(), any()) } returns Unit
+        val activity = mockk<MainActivity>(relaxed = true)
+        every { activity.isChangingConfigurations } returns false
+        every { activity invoke "onStop" withArguments emptyList() } answers { callOriginal() }
+
+        invokeLifecycle(activity, "onStop")
+
+        verify(exactly = 1) { NotificationHelper.setAppForeground(activity, false) }
+    }
+
+    private fun invokeLifecycle(
+        activity: MainActivity,
+        method: String,
+    ) {
+        try {
+            MainActivity::class.java
+                .getDeclaredMethod(method)
+                .apply { isAccessible = true }
+                .invoke(activity)
+        } catch (error: InvocationTargetException) {
+            // Execute real app code; only the trailing Android framework stub is unavailable on the JVM.
+            val expected = "Method $method in android.app.Activity not mocked."
+            if (error.targetException.message?.startsWith(expected) != true) throw error
+        }
+    }
+}