[Pyodide] RFC: Improve PyProxy lifetime management when calling Javascript functions from Python

Hey folks,

I wrote a proposal to improve PyProxy lifetime management.

The proposal is here: https://github.com/pyodide/pyodide/issues/1607

An implementation is here: https://github.com/pyodide/pyodide/pull/1573

Please let us know what you think (preferably by commenting on the github issue).

Hood