Making template/target execution statistics configurable for normal build

[Deamhan]

Hi, I'd like to discuss the idea of merging build-stats and build options with additional command like string argument, containing directory we want to save events.jsonl. For example if this directory is empty we can skip logging and system will work the same way it works now, but if we set this argument we'll store events inside of it. Something like

flagSet.StringVarP(&options.DetailedStatsFolder, "detailed-stats", "ds", "", "folder to store detailed timing and performance tracking per template"),

and in code

if r.options.DetailedStatsFolder != "" {
events.InitWithConfig(&events.ScanConfig{

couple of additional minor changes are required, but I've already using such modified build and can provide a full patch if the idea will be accepted.