Fry3DX 0.5: builds for Windows, Linux and Android, a phone layout, Apache 2.0

- Apache License 2.0
- Windows: cross-built with clang-cl (cmake --preset windows), a window
  program with its icon; Linux: a portable preset (SDL and the C++
  library inside); Android: android/build_apk.py makes the APK
- tools/package.py packs the downloads; a GitHub workflow builds all
  three and makes a release for a v* tag
- A phone layout (fry_touch, on by default on Android): the UI drawn
  bigger, panels when asked for, a bar of big buttons, one finger to
  turn the view, two to move and pinch, a long press for a right-click;
  files through the phone's file picker
- Settings and autosaves now in a Nexoniarz folder (copied over once)
- README rewritten, the website shows the downloads and the phone

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NMSrd5oe1GpUD7E6d825KP

android/java/io/github/nexoniarz/fry3dx/FryActivity.java

@@ -0,0 +1,11 @@
+package io.github.nexoniarz.fry3dx;
+
+import org.libsdl.app.SDLActivity;
+
+// Fry3DX's activity: SDL's, loading SDL and the app (libmain.so, whose SDL_main it runs).
+public class FryActivity extends SDLActivity {
+    @Override
+    protected String[] getLibraries() {
+        return new String[] {"SDL3", "main"};
+    }
+}