owner limit

[rouzwelt]

Motivation

resolves #237

Solution

makes rounds stateful by keeping a map of orderbooks -> owner -> owner profile -> orders -> pairs and sequentionaly select orders based on each owner's limit for the upcoming round.
this means that we cant have distinct sg query for orders on each round, since that completely collides with statefulness of owner's orders between rounds, so at startup, the orders are fetched once and after that we set watchers for orderbooks add/remove order events and apply the new changes to the map at end of every round.
this as a result minimizes the use subgraph to great extent, since there will only ne one query only at startup.

Edit1:

Reading new order changes from rpc by listening to orderbook onchain events requires a reliable rpc, so no orders changes are missed and we dont get rpc errors, since we dont have reliable rpc solution at this point, reverted back to using sg instead, which is a more reliable source at this point, we query sg for order changes on every round for the specific timeframe, basically similar to listening on onchain events, but rather querying the sg for AddOrder and RemoveOrder entities, and keep track of changes returned by the query.

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