SQL Expressions: Re-implement feature using go-mysql-server (#99521)

* Under feature flag `sqlExpressions` and is experimental
* Excluded from arm32
* Will not work with the Query Service yet
* Does not have limits in place yet
* Does not working with alerting yet
* Currently requires "prepare time series" Transform for time series viz
 
---------

Co-authored-by: Sam Jewell <sam.jewell@grafana.com>

pkg/expr/converter.go

@@ -23,7 +23,6 @@ type ResultConverter struct {
 func (c *ResultConverter) Convert(ctx context.Context,
 	datasourceType string,
 	frames data.Frames,
-	allowLongFrames bool,
 ) (string, mathexp.Results, error) {
 	if len(frames) == 0 {
 		return "no-data", mathexp.Results{Values: mathexp.Values{mathexp.NewNoData()}}, nil
@@ -80,7 +79,7 @@ func (c *ResultConverter) Convert(ctx context.Context,
 			continue
 		}
 
-		if schema.Type != data.TimeSeriesTypeWide && !allowLongFrames {
+		if schema.Type != data.TimeSeriesTypeWide {
 			return "", mathexp.Results{}, fmt.Errorf("%w but got type %s (input refid)", ErrSeriesMustBeWide, schema.Type)
 		}
 		filtered = append(filtered, frame)