Support filtering in builtin notebook variable view

[rebornix]

The builtin Variable View for notebook now lists all "variables" from the Jupyter kernel right now, most of which are contributed by Jupyter extension or the Kernel

It would be great if we can support filtering the variables:

• Support "My Variables Only"
• Support filtering based on types (Module, Class, etc)
• Exclude the builtin function/modules contributed by Jupyter extension (e.g., chat)

[rebornix]

Another solution @amunger mentioned is filtering or grouping them in Jupyter (variable provider)