extract kindsys to external library (#64562)

* extract kindsys

* reinstate kindsys report

This may end up living somewhere else (or not! who knows!), but the important part is that I don't get rid of it right now :)

I hate the package layout (kindsysreport/codegen) for the main function and will take pretty much any alternative suggestion, but we can change also change it later.

Note that the generated report.json is in a different location - anything using this (ops something) needs to be updated.

* kindsysreport in codeowners

pkg/codegen/tmpl.go

@@ -7,7 +7,7 @@ import (
 	"time"
 
 	"github.com/grafana/codejen"
-	"github.com/grafana/grafana/pkg/kindsys"
+	"github.com/grafana/kindsys"
 )
 
 // All the parsed templates in the tmpl subdirectory