pyodide: Bug: Syntax error handling in console.html

The why it happens only for syntax errors (and not runtime errors) can be understood with this three lines:

    const prompt = pyconsole.push(c) ? ps2 : ps1;
    term.set_prompt(prompt);
    await pyconsole.run_complete;

Execution steps for runtime errors (or even code exec without any error) are:

1. pyconsole.push(c) returns false (code is not yet executed)
2. prompt is set to >>>
3. code is executed (via the run_complete promise), error is printed to stderr
4. JQuery Terminal shows it by setting the prompt.

While for syntax error, we have:

1. pyconsole.push(c) prints syntax error to stderr (and return false)
2. JQuery Terminal shows it by setting the prompt
3. prompt is erased by our call to set_prompt
4. run_complete is a dummy promise so the await has no effect.

I opened a PR: https://github.com/jcubic/jquery.terminal/pull/652

I think I got it. In console.html, we continuously set the prompt:

async function interpreter(command) {
    // multiline should be splitted (usefull when pasting)
    term.pause();
    for( const c of command.split('\n') ) {
        const prompt = pyconsole.push(c) ? ps2 : ps1;
        term.set_prompt(prompt);
        await pyconsole.run_complete;
    }
    term.resume();
}

which disturb echo_newline.js since it also set the prompt…