build(android): 生成原生Android工程 — Android Studio直接构建

- android/: 完整Gradle工程(build.gradle/settings/AndroidManifest/Activity/Application)
- PackageInstallerModule: 重写为ReactContextBaseJavaModule (bare RN, 移除Expo依赖)
- 新增sha256File原生方法, installApk改为Promise异步
- 移除旧的modules/ (Expo Module → bare React Native)
- 添加eas.json (备用云端构建)

packages/client-android/android/app/build.gradle

@@ -0,0 +1,38 @@
+apply plugin: "com.android.application"
+apply plugin: "org.jetbrains.kotlin.android"
+
+android {
+    namespace "dev.yuzu.gca"
+    compileSdk rootProject.ext.compileSdkVersion
+
+    defaultConfig {
+        applicationId "dev.yuzu.gca"
+        minSdk rootProject.ext.minSdkVersion
+        targetSdk rootProject.ext.targetSdkVersion
+        versionCode 4
+        versionName "0.1.0"
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+        }
+        debug {
+            debuggable true
+        }
+    }
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_17
+        targetCompatibility JavaVersion.VERSION_17
+    }
+
+    kotlinOptions {
+        jvmTarget = "17"
+    }
+}
+
+dependencies {
+    implementation("com.facebook.react:react-android")
+    implementation("com.facebook.react:hermes-android")
+}