Radar tile cadence and caching?

[jpettitt]

Hi, I'm the maintainer of the home assistant weather-radar-card. In debugging some issue I'm seeing two problems

1. I can't find an endpoint that I can use to tell me the available radar tiles so we're essentially guessing on availability
2. Radar tiles are served with cache-control: private and no Etag or last modified so we end reloading data what ideally should be in browser cache.

Any suggestion of how to fix?

For ref this is what the home assistant map looks like with watches and warnings turned on, wild fire data, and live lightning data from Blitzortung.