polish(api): expose filReserveDisbursed via CirculatingSupply API

- motivated by: https://github.com/filecoin-project/sentinel-visor/issues/462

api/api_full.go

@@ -1004,6 +1004,7 @@ type CirculatingSupply struct {
 	FilBurnt            abi.TokenAmount
 	FilLocked           abi.TokenAmount
 	FilCirculating      abi.TokenAmount
+	FilReserveDisbursed abi.TokenAmount
 }
 
 type MiningBaseInfo struct {

chain/stmgr/stmgr.go

@@ -1284,6 +1284,7 @@ func (sm *StateManager) GetVMCirculatingSupplyDetailed(ctx context.Context, heig
 		FilBurnt:            filBurnt,
 		FilLocked:           filLocked,
 		FilCirculating:      ret,
+		FilReserveDisbursed: filReserveDisbursed,
 	}, nil
 }