* Add log message when discarding recording segments in cache
Currently Frigate silently discards recording segments in cache if there's more than "keep_count" for a camera, which can happen on high load/busy/slow systems.
This results in recording segments being lost with no apparent cause in the logs (even when set to debug).
This PR adds a warning log entry when discarding segments, in the same way as discarding corrupted segments
* Add explanatory warning and properly format cache_path warning
* lint fixes
Co-authored-by: Blake Blackshear <blakeb@blakeshome.com>
