Test backup: run every configured mechanism, stop misreporting passphrase-only as unconfigured

The user's report: with only a backup passphrase set (no S3), 'Test
backup nå' errored 'ikke konfigurert' even though Google Auto Backup
works on the passphrase alone. New runConfiguredBackups() writes the
Google blob whenever a passphrase exists and uploads to S3 only when
those credentials are present, throwing only when NOTHING is set up.
The toast now names what actually ran ('Kryptert Google-kopi
oppdatert' and/or the bucket key). Two instrumented tests pin both
ends: passphrase-only succeeds, nothing-configured throws.

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

app/src/androidTest/java/no/naiv/meddetsamme/backup/CloudBackupRoundTripTest.kt

@@ -86,6 +86,26 @@ class CloudBackupRoundTripTest {
         assertTrue("DB still empty after failed restore", db.inventoryDao().getAll().isEmpty())
     }
 
+    @Test fun testBackupWithOnlyPassphraseSucceeds() = runBlocking {
+        // The user's report: passphrase set, no S3 → "Test backup" must NOT
+        // error with "not configured"; it writes the Google blob and says so.
+        SettingsStore(context).autoBackupPassphrase = "x"
+        db.inventoryDao().insert(InventoryItem(name = "A", strength = "", unit = "stk", form = MedForm.OTHER))
+
+        val outcome = manager.runConfiguredBackups()
+        assertTrue("cloud blob written", outcome.cloudBlobWritten)
+        assertNull("no S3 attempted when unconfigured", outcome.s3Key)
+        assertTrue(BackupManager.cloudBlobFile(context).exists())
+    }
+
+    @Test fun testBackupWithNothingConfiguredThrows() = runBlocking {
+        SettingsStore(context).autoBackupPassphrase = null
+        try {
+            manager.runConfiguredBackups()
+            org.junit.Assert.fail("must require at least one mechanism")
+        } catch (_: IllegalArgumentException) { /* expected */ }
+    }
+
     @Test fun noPassphraseRemovesBlob() = runBlocking {
         SettingsStore(context).autoBackupPassphrase = "x"
         db.inventoryDao().insert(InventoryItem(name = "A", strength = "", unit = "stk", form = MedForm.OTHER))