Pyodide Conversion: add ability to include resources for the panel app

[flxmr]

Is your feature request related to a problem? Please describe.

I want to package a panel which is essentially a fancy mailmerge app to pyodide. Unfortunately there is no way to include template files into the panel app.

Describe the solution you'd like

• add a CLI switch --ressources which takes a list of files and folder which should be available to Pyiodide
• package those into a zipfile
• modify convert_app in convert.py to unpack the zipfile into the WASM environment:

  await pyodide.runPythonAsync(`
     from pyodide.http import pyfetch
     response = await pyfetch("http://localhost:8000/appfiles.zip")
     await response.unpack_archive()
    `);

[flxmr]

https://github.com/holoviz/panel/issues/4164 and obviously this is a duplicate ;)