Come up with URL parameter scheme

Ideally, any given interesting view should be linkable both for sharing and for permalinking. streamlit does of course provide experimental_get_query_params, but to use it for anything useful, we need - for each page - to define exactly what needs to be specified for a given view.

Example: simple_constant_view just needs one CCV ID. So that page already has the ccv_id parameter. The same could be done for bad_pixel_trends.

On the other hand, assembled_constant_preview needs a detector and one constant for each module to assemble. And maybe a timestamp? In total, we need to be told or able to infer (via configuration / PDU mapping / other metadata from CalCat) which CCV ID to put into which part of the geometry. Though it's easy to support custom geometry, I don't think we'll want to base64-encode this into the URL (though we could).

Whichever scheme we come up with should tie into #2 (closed)