fix(android): UPnP - add kxml2 to test classpath so DeviceDescriptionTest runs

Android's XmlPullParserFactory is a Stub-throwing class in android.jar
on the JVM unit-test classpath; the probe pattern from dc5b8252 was
silently skipping the test suite, which gives false test-coverage
confidence. kxml2 is the same parser implementation Android uses
internally - service-provider lookup picks it up automatically once
on the test classpath.

The probe + Assumptions.assumeTrue skip removed; tests now run
unconditionally.

testImplementation(libs.kxml2) - 2.3.0, MIT-licensed, ~80KB. No
production code change.

android/app/src/test/java/com/fabledsword/minstrel/player/output/upnp/DeviceDescriptionTest.kt

@@ -1,10 +1,7 @@
 package com.fabledsword.minstrel.player.output.upnp
 
 import okhttp3.HttpUrl.Companion.toHttpUrl
-import org.junit.jupiter.api.Assumptions.assumeTrue
-import org.junit.jupiter.api.BeforeEach
 import org.junit.jupiter.api.Test
-import org.xmlpull.v1.XmlPullParserFactory
 import kotlin.test.assertEquals
 import kotlin.test.assertNotNull
 import kotlin.test.assertNull
@@ -14,23 +11,14 @@ import kotlin.test.assertNull
  *
  * Android's stock `XmlPullParserFactory.newInstance()` resolves to a
  * real impl on-device but resolves to the android.jar stub class on
- * JVM unit tests unless an org.xmlpull impl (kxml2) is present on the
- * test classpath. The @BeforeEach probe skips the suite gracefully on
- * runners where the factory can't be constructed — keeps CI green on
- * minimal classpaths while still running the assertions when the
- * impl IS available (Android instrumentation, Robolectric, or any
- * runner that bundles kxml2 transitively).
+ * JVM unit tests. kxml2 is added as a testImplementation dep so
+ * `XmlPullParserFactory.newInstance()` finds it via service-provider
+ * lookup on the test classpath; the tests run unconditionally.
  */
 class DeviceDescriptionTest {
 
     private val base = "http://192.168.1.50:1400/xml/device_description.xml".toHttpUrl()
 
-    @BeforeEach
-    fun skipIfStubFactory() {
-        val ok = runCatching { XmlPullParserFactory.newInstance().newPullParser() }.isSuccess
-        assumeTrue(ok, "XmlPullParserFactory unavailable on this JVM classpath")
-    }
-
     @Test
     fun `parses Sonos-shaped description`() {
         val xml = """