Fix Android WebView API access and mobile shell layout

front/android/build.gradle

@@ -0,0 +1,31 @@
+// Top-level build file where you can add configuration options common to all sub-projects/modules.
+
+buildscript {
+    def googleMirror = 'https://maven.aliyun.com/repository/google'
+
+    repositories {
+        maven { url googleMirror }
+        mavenCentral()
+    }
+    dependencies {
+        classpath 'com.android.tools.build:gradle:8.13.0'
+
+        // NOTE: Do not place your application dependencies here; they belong
+        // in the individual module build.gradle files
+    }
+}
+
+apply from: "variables.gradle"
+
+allprojects {
+    def googleMirror = 'https://maven.aliyun.com/repository/google'
+
+    repositories {
+        maven { url googleMirror }
+        mavenCentral()
+    }
+}
+
+task clean(type: Delete) {
+    delete rootProject.buildDir
+}