schema: Migrate from scuemata to thema (#49805)

* Remove crufty scuemata bits

Buhbye to: cue/ dir with old definitions, CI steps for checking unnecessary
things, and the original dashboard scuemata file.

* Remove grafana-cli cue subcommand

* Remove old testdata

* Don't swallow errors from codegen

* Small nits and tweaks to cuectx package

* WIP - refactor pluggen to use Thema

Also consolidate the embed.FS in the repo root.

* Finish halfway rename

* Convert all panel models.cue to thema

* Rewrite pluggen to use Thema

* Remove pkg/schema, and trim command

* Remove schemaloader service and usages

Will be replaced by coremodel-centric hydrate/dehydrate system Soon™.

* Remove schemaloader from wire

* Remove hangover field on histogram models.cue

* Fix lint errors, some vestiges of trim service

* Remove unused cuetsify cli command

pkg/api/dashboard.go

@@ -58,20 +58,12 @@ func (hs *HTTPServer) TrimDashboard(c *models.ReqContext) response.Response {
 	if err := web.Bind(c.Req, &cmd); err != nil {
 		return response.Error(http.StatusBadRequest, "bad request data", err)
 	}
-	var err error
 	dash := cmd.Dashboard
 	meta := cmd.Meta
 
-	trimedResult := *dash
-	if !hs.LoadSchemaService.IsDisabled() {
-		trimedResult, err = hs.LoadSchemaService.DashboardTrimDefaults(*dash)
-		if err != nil {
-			return response.Error(500, "Error while exporting with default values removed", err)
-		}
-	}
-
+	// TODO temporarily just return the input as a no-op while we convert to thema calls
 	dto := dtos.TrimDashboardFullWithMeta{
-		Dashboard: &trimedResult,
+		Dashboard: dash,
 		Meta:      meta,
 	}