Improve JavaScript error management

[Angelmmiguel]

JavaScript handlers are run in WebAssembly using a module based on QuickJS. When an error appear, it's complex to debug as we are running an interpreter inside a Wasm module while adding a compatibility layer.

To improve this experience, the JavaScript error must be captured on the rust server and printed.

It's still under discussion if we want to show these error traces always or behind a CLI flag.