feat: add a cache for last value result in row group (#4369)

* feat: add selector result cache to cache manager

* feat: expose config

src/store-api/src/storage/requests.rs

@@ -17,7 +17,7 @@ use datafusion_expr::expr::Expr;
 use strum::Display;
 
 /// A hint on how to select rows from a time-series.
-#[derive(Clone, Debug, PartialEq, Eq, Display)]
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Display)]
 pub enum TimeSeriesRowSelector {
     /// Only keep the last row of each time-series.
     LastRow,