Overhaul HLS streaming (#3274)

* Overhaul HLS streaming
* Fix streaming transcode ffmpeg zombie processes
* Add changelog and release notes
* Documentation
---------
Co-authored-by: WithoutPants <53250216+WithoutPants@users.noreply.github.com>

internal/api/resolver_mutation_configure.go

@@ -123,6 +123,7 @@ func (r *mutationResolver) ConfigureGeneral(ctx context.Context, input ConfigGen
 		c.Set(config.Metadata, input.MetadataPath)
 	}
 
+	refreshStreamManager := false
 	existingCachePath := c.GetCachePath()
 	if input.CachePath != nil && existingCachePath != *input.CachePath {
 		if err := validateDir(config.Cache, *input.CachePath, true); err != nil {
@@ -130,6 +131,7 @@ func (r *mutationResolver) ConfigureGeneral(ctx context.Context, input ConfigGen
 		}
 
 		c.Set(config.Cache, input.CachePath)
+		refreshStreamManager = true
 	}
 
 	if input.VideoFileNamingAlgorithm != nil && *input.VideoFileNamingAlgorithm != c.GetVideoFileNamingAlgorithm() {
@@ -328,6 +330,9 @@ func (r *mutationResolver) ConfigureGeneral(ctx context.Context, input ConfigGen
 	if refreshScraperCache {
 		manager.GetInstance().RefreshScraperCache()
 	}
+	if refreshStreamManager {
+		manager.GetInstance().RefreshStreamManager()
+	}
 
 	return makeConfigGeneralResult(), nil
 }