android: only enable CoreSideloadActivity on debug builds (#20024)

pkg/android/phoenix/AndroidManifest.xml

@@ -52,7 +52,6 @@
                 <category android:name="tv.ouya.intent.category.GAME" />
             </intent-filter>
         </activity-alias>
-        <activity android:name="com.retroarch.browser.debug.CoreSideloadActivity" android:exported="true"/>
         <receiver android:name="com.retroarch.browser.receiver.InstalledCoresReceiver" android:exported="true">
             <intent-filter>
                 <action android:name="com.retroarch.QUERY_INSTALLED_CORES" />

pkg/android/phoenix/build.gradle

@@ -160,6 +160,12 @@ android {
       jni.srcDirs = []
       res.srcDirs = ['res', '../phoenix-common/res']
     }
+    debug {
+      manifest.srcFile 'src/debug/AndroidManifest.xml'
+    }
+    release {
+      manifest.srcFile 'src/release/AndroidManifest.xml'
+    }
     normal {
       java.srcDirs += ['../play-core-stub']
     }

pkg/android/phoenix/src/debug/AndroidManifest.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <application>
+        <!-- Debug-only activity for core sideloading -->
+        <activity android:name="com.retroarch.browser.debug.CoreSideloadActivity" android:exported="true"/>
+    </application>
+</manifest>

pkg/android/phoenix/src/release/AndroidManifest.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <application>
+        <!-- Release builds exclude debug activities -->
+    </application>
+</manifest>