[TASK] Execute Custom JS code in Jupyter Lab

[CermakM]

User story
As a user of this extension
I want to be able to use this extension in Jupyter Lab
so that I could execute custom JS code snippets

Acceptance Criteria

• The extension can be loaded into Jupyter Lab environment using the %load_ext magic
• Custom libraries can be loaded into the context using the magic commands
• Custom JS can be executed in Jupyter Lab
• The custom script can make use of the libraries/modules loaded by the extension

Linked epics / issues
#7