Extend KV store docs with examples in Python and JS

[TC-MO]

Based on discord ask, it seems like users could not figure out how to utilize KV store to save images and others.

We should extend the documentation with some examples of implementation in both Python and JS.

The discord ask in question

Hi, I read the documentation on keyvalue pair storage, but did not quite really figure out how to use it to store images, videos or audio using python sdk. Is there any example code that I can reference to?