android-native: SDL3 APK build for the native client

build-android-native.sh downloads SDL 3.4.16 (sha256-checked), builds
libSDL3.so and libmain.so (native_render + port_platform + embedded
Python) at API 24, and wraps them in the SDLActivity shell under
android-native/ (package org.metin2port.client). push-android-client.sh
copies the 40250 Client directory into the app's files/ with run-as
(--locale XX selects locale_XX.cfg). port_logic links with
--no-dependent-libraries on ELF targets so the verbatim
`#pragma comment(lib, ...)` lines do not break lld.

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

.gitignore

@@ -78,3 +78,10 @@ __pycache__/
 
 # Written by 40250 uitaskbar.py (SaveMouseButtonSettings) into the working directory at runtime.
 /project/mouse.cfg
+
+# native Android client (./build-android-native.sh): SDL3 download, NDK builds, Gradle output
+/build-android-native/
+/android-native/.gradle/
+/android-native/app/build/
+/android-native/build/
+/android-native/local.properties