Increase Emscripten stack size (+options update)

[Daft-Freak]

Default stack was decreased in emscripten-core/emscripten@157fcd4. 64k results in screen corruption in even the most minimal example, 256k is enough to fix this but increase to 1MB to be safe. (Old default was 5MB)

Also clean up to use the preferred -sTHING= syntax and remove the EXTRA_ from EXPORTED_RUNTIME_METHODS.

[Gadgetoid]

Thank you!

I went to grab a zip of build artifacts to try- force of habit from Pico- but there are none 😢 I don't think there's a reason for this? I'll raise a PR to add them when I get a moment.

Built it locally- taking an opportunity to test the guide- and it all looks good!

[Daft-Freak]

Yeah, I don't think there's a reason for not having artifacts either... other than nobody thought of adding them (and maybe that the CI was travis at one point)

Artifacts for the emscripten build will be slightly harder as you can't just install to get all the files. (cmake doesn't understand that the "executable" is three files...)

[ahnlak]

You can just add install(FILES ... instructions to CMake to get it to add in the extra bits though (I think I've done this in Another Project and it seemed to work)

[Daft-Freak]

You can do that... and I forgot that we already are:

32blit-sdk/32blit-sdl/CMakeLists.txt

Lines 187 to 189 in 3c6de84

	install(FILES ${CMAKE_CURRENT_BINARY_DIR}/${NAME}.js ${CMAKE_CURRENT_BINARY_DIR}/${NAME}.wasm
	DESTINATION bin
	)

So uh, ignore that comment.