Add Prometheus Metrics for Cache Usage

[mastercactapus]

What problem would you like to solve? Please describe: There is currently no easy way to monitor how effectively our caches are being used. This could lead to inefficient cache utilization and can impact performance decisions.

Describe the solution you'd like: I propose that we add Prometheus metrics for the places we're using caches. This should at least include basic details like hit/miss ratios and possibly the size of the caches. This would allow us to monitor cache performance more easily in a standardized way, and help us make better decisions regarding cache use in the future.

Additional context: The addition of such metrics will provide insights into the inner workings of the caching mechanism, providing better observability of the system in general.