Huge refactor to api and add batch api

script/sql/create/5.pipes.sql

@@ -12,4 +12,5 @@ create table pipes
 , roughness numeric not null
 , minor_loss numeric not null
 , status pipes_status not null
+, check (node1 <> node2)
 );

script/sql/create/operation.sql

@@ -5,11 +5,11 @@ create table operation
 , undo text not null
 , parent integer references operation(id) on delete cascade
 , redo_child integer references operation(id) -- must update before delete
-, redo_change_set jsonb
-, undo_change_set jsonb
+, redo_cs text not null
+, undo_cs text not null
 );
 
-insert into operation (id, redo, undo) values (0, '', '');
+insert into operation (id, redo, undo, redo_cs, undo_cs) values (0, '', '', '', '');
 
 create table current_operation
 (