Test infra: add Compose UI Test + UI Automator to androidInstrumentedTest

Prep for parallel Android UI test suite build-out. These deps unblock
page-object tests using onNodeWithTag / createAndroidComposeRule and
cross-app permission-dialog interaction.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

composeApp/build.gradle.kts

@@ -141,6 +141,8 @@ kotlin {
                 implementation(libs.androidx.espresso.core)
                 implementation(libs.androidx.test.runner)
                 implementation(libs.mockk.android)
+                implementation(libs.compose.ui.test.junit4.android)
+                implementation("androidx.test.uiautomator:uiautomator:2.3.0")
             }
         }
     }