SSE: Use errutil to show better error messages in prod (#71658)

- include public message
- propagate data source query errors so they are shown as well to which fixes #70026

pkg/expr/nodes_test.go

@@ -26,28 +26,19 @@ func (e expectedError) Error() string {
 }
 
 func TestQueryError_Error(t *testing.T) {
-	e := QueryError{
-		RefID: "A",
-		Err:   errors.New("this is an error message"),
-	}
-	assert.EqualError(t, e, "failed to execute query A: this is an error message")
+	e := MakeQueryError("A", "", errors.New("this is an error message"))
+	assert.EqualError(t, e, "[sse.dataQueryError] failed to execute query [A]: this is an error message")
 }
 
 func TestQueryError_Unwrap(t *testing.T) {
 	t.Run("errors.Is", func(t *testing.T) {
 		expectedIsErr := errors.New("expected")
-		e := QueryError{
-			RefID: "A",
-			Err:   expectedIsErr,
-		}
+		e := MakeQueryError("A", "", expectedIsErr)
 		assert.True(t, errors.Is(e, expectedIsErr))
 	})
 
 	t.Run("errors.As", func(t *testing.T) {
-		e := QueryError{
-			RefID: "A",
-			Err:   expectedError{},
-		}
+		e := MakeQueryError("A", "", expectedError{})
 		var expectedAsError expectedError
 		assert.True(t, errors.As(e, &expectedAsError))
 	})