Android: Update dependencies and build tools

Update Android dependencies and build tools to their latest available versions.

Rename the GameCube save magic constant to avoid a collision with the NDK 30 ARM64 signal context header.

Source/Android/settings.gradle.kts

@@ -1,19 +1,4 @@
 pluginManagement {
-    buildscript {
-        repositories {
-            mavenCentral()
-            maven {
-                url = uri("https://storage.googleapis.com/r8-releases/raw")
-            }
-        }
-        dependencies {
-            // Temporary override for AGP-bundled R8 crash in release minification.
-            // https://issuetracker.google.com/issues/495458806
-            // TODO: Re-test without this override when upgrading AGP and remove if fixed upstream.
-            classpath("com.android.tools:r8:9.1.34")
-        }
-    }
-
     repositories {
         gradlePluginPortal()
         google()