android: build.sh installs and syncs the game files when a phone is attached

After building the APK, android/build.sh now picks the attached device (ANDROID_SERIAL for several),
installs the APK (reinstalling on a signature mismatch), syncs the zh client into files/Client and, with
--launch, wakes the phone and starts the app. Without a device it only builds.

push-client.sh is now incremental (android/sync_client.py): the device keeps files/Client/.mt_sync
(size, mtime, path of what the last sync wrote), so later syncs send only new and changed files as one
tar streamed through `adb shell -T run-as` (no copy in /data/local/tmp) and delete the ones gone
locally. Only game resources are synced; settings and logs the app writes there are kept. --locale zh
rebuilds build/zh-locale/Client first when its inputs changed. android/adb_env.sh picks adb and falls
back to server port 5038 when :5037 cannot bind.

Verified against a fake adb device: first sync (1.4 GB, byte-identical), no-op resync, changed files,
deletions, locale switch, --full, the install/launch path and the no-device path.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/PORT-PLAN.md

@@ -204,8 +204,8 @@ PORT 扩展（40250 没有对应物，只为移动端/平台而加；不能改 4
 - macOS：`brew install cmake sdl3 vulkan-headers vulkan-loader molten-vk shaderc`；构建见根目录 README
   （`-DMT_BUILD_NATIVE_RENDER=ON`，目标 `mt_native_render`）。
 - Android：NDK 27.2（`ANDROID_NDK_HOME` 指向它）、openjdk@21、Android SDK；`adb` 用 `/opt/homebrew/bin/adb`。
-  `./android/build.sh Release --install` 构建安装 APK，`./android/push-client.sh [--locale zh] <Client>` 推送资源
-  （APK 只含代码，资源在应用数据目录）。启动前先唤醒手机。
+  `./android/build.sh [--launch]` 构建 APK，连着手机时自动安装并增量同步中文资源（`android/push-client.sh`；
+  APK 只含代码，资源在应用数据目录）。启动前先唤醒手机。
 - Python 3：用于 `port_map.py` 和其他审计脚本。Python 2.7.18 只在复核 `py_embed_spike.py` 时需要。
 - 真服账号、密码不写进仓库或 audit 账本。