test: replace placeholder smoke with permission-rationale assert

app/src/androidTest/java/de/jeanlucmakiola/calendula/MainActivitySmokeTest.kt

@@ -4,23 +4,27 @@ import androidx.compose.ui.test.assertIsDisplayed
 import androidx.compose.ui.test.junit4.createAndroidComposeRule
 import androidx.compose.ui.test.onNodeWithText
 import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.platform.app.InstrumentationRegistry
 import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
 
+/**
+ * Smoke: launches MainActivity and asserts the permission rationale renders
+ * when calendar access has not yet been granted. Without GrantPermissionRule
+ * the system reports NOT_GRANTED on first launch so we land in PermissionScreen.
+ */
 @RunWith(AndroidJUnit4::class)
 class MainActivitySmokeTest {
 
     @get:Rule
     val composeTestRule = createAndroidComposeRule<MainActivity>()
 
-    @Test
-    fun appName_isDisplayed_onLaunch() {
-        composeTestRule.onNodeWithText("Calendula").assertIsDisplayed()
-    }
+    private val res = InstrumentationRegistry.getInstrumentation().targetContext.resources
 
     @Test
-    fun tagline_isDisplayed_onLaunch() {
-        composeTestRule.onNodeWithText("A modern calendar.").assertIsDisplayed()
+    fun permissionRationale_isDisplayed_onLaunch_withoutPermission() {
+        composeTestRule.onNodeWithText(res.getString(R.string.permission_rationale_title))
+            .assertIsDisplayed()
     }
 }