fix(android): force landscape from launch

WackiActivity was already sensorLandscape, but SetupActivity (the
launcher) had no orientation, so the app opened in the system orientation
(often portrait) before the game flipped to landscape. Force
sensorLandscape on SetupActivity too, and set SDL_HINT_ORIENTATIONS to
landscape-only in the Android early-init so SDL's runtime orientation pick
can't request portrait. The app is now landscape from the first frame.

Author: mszula

android/app/src/main/AndroidManifest.xml

@@ -22,6 +22,7 @@
             android:name=".SetupActivity"
             android:exported="true"
             android:theme="@android:style/Theme.Material.Light"
+            android:screenOrientation="sensorLandscape"
             android:configChanges="orientation|screenSize|keyboardHidden">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />

src/platform/sdl/system_sdl.c

@@ -69,6 +69,11 @@ void plat_system_early_init(void)
     if (home && chdir(home) == 0)
         LOG_INFO("platform", "user dir: %s", home);
     SDL_SetHint(SDL_HINT_ANDROID_TRAP_BACK_BUTTON, "1");
+    /* Lock to landscape. The manifest already forces it per-activity; this
+     * pins SDL's own runtime orientation pick (it sets the activity's
+     * requested orientation when the 640×480 window is created) to landscape
+     * only, so a device held in portrait never flashes/rotates the game. */
+    SDL_SetHint(SDL_HINT_ORIENTATIONS, "LandscapeLeft LandscapeRight");
 #endif
 }