add android jni (#1340)

easytier-contrib/easytier-android-jni/kotlin/com/easytier/jni/README.md

@@ -0,0 +1,41 @@
+# 使用说明
+
+1. 需要将 proto 文件放入 app/src/main/proto
+2. android/gradle/libs.versions.toml 中加入依赖
+
+```
+# Wire 核心运行时
+android-wire-runtime = { group = "com.squareup.wire", name = "wire-runtime", version = "5.3.11" }
+moshi = { module = "com.squareup.moshi:moshi", version.ref = "moshi" }
+android-wire-moshi-adapter = { group = "com.squareup.wire", name = "wire-moshi-adapter", version = "5.3.11" }
+kotlinx-serialization-json = { group = "org.jetbrains.kotlinx", name = "kotlinx-serialization-json", version = "1.9.0" }
+```
+
+3. build.gradle.kts 中加入
+
+```
+plugins {
+    ...
+    alias(libs.plugins.wire)
+}
+
+dependencies {
+    ...
+    implementation(libs.android.wire.runtime)
+    implementation(libs.android.wire.moshi.adapter)
+    implementation(libs.moshi)
+}
+
+...
+
+wire {
+    kotlin {
+        rpcRole = "none"
+    }
+}
+```
+
+4. 调用 easytier-contrib/easytier-android-jni/build.sh 生成 jni 和 ffi 的 so 文件。
+并将生成的 so 文件放到 android/app/src/main/jniLibs/arm64-v8a 目录下。
+
+5. 使用 EasyTierManager 可以拉起 EasyTier 实例并启动 Android VpnService 组件。