CI enhancements: app bundling, build wasm

[iceiix]

Update configuration for GitHub Actions:

• Add macos .app bundling, fixes CI/CD consolidation/enhancements: macOS .app bundling #352
• Add web wasm building 🕸️ Web support 🕸️ Web support #446

[iceiix]

Trying to create an .app bundle for macos-latest, built using https://github.com/burtonageo/cargo-bundle. It builds (locally) but when I double-click to run it, nothing happens. cargo bundle --example hello in https://github.com/burtonageo/cargo-bundle, in contrast, does build a working .app (was an icon and everything, showing a simple winit window).

cargo bundle --release
target/release/bundle/osx/Stevenarella.app/Contents/MacOS/stevenarella # runs ok
target/release/bundle/osx/Stevenarella.app # nothing?
open -R target/release/bundle/osx/Stevenarella.app # then double-click: nothing

Adding code in src/main.rs to write to a file, confirms the code is executed, just no window pops up...

Logging to a file (#359) would be helpful here to debug further

But the problem is the current working directory, std::env::current_dir() shows it is set to "/". Setting with std::env::set_current_dir() to a hardcoded path with the assets fixes the launch problem. Setting cwd to the same directory as the executable works:

⚠     if let Some(parent) = std::env::current_exe().unwrap().parent() {
⚠         std::env::set_current_dir(parent);
      }  

but then it downloads index/objects into Contents/MacOS. An app-specific prefs dir would make more sense, but on the other hand when launched from the CLI, or from Linux, may make sense to leave it as the current directory..