Add venue config option for IB

[sunlei]

Pull Request

• I have reviewed the CONTRIBUTING.md and followed the established practices

Summary

Add venue config option for IB.

Type of change

• New feature (non-breaking)

[faysou]

I don't think it makes sense to use another value than IB_VENUE for IB, the whole adapter needs this constant. Because account updates from IB come for the full IB, it's not by venue, or sub venue, and we use IB_VENUE as convention. IB_VENUE is used as constant in other places in the system, in the cache and the risk engine. So basically the IB adapater shouldn't be used with another venue as config.

[sunlei]

@faysou

This PR is similar to a previously merged one: #1738

In the IB-based strategy I'm currently developing, I need to operate multiple accounts within a single strategy to perform order-related operations.

I made these changes to allow configuring multiple clients in TradingNodeConfig.exec_clients, as shown in the example below:

exec_clients={
    "IB_ACCOUNT_1": InteractiveBrokersExecClientConfig(
        venue=Venue("IB_ACCOUNT_1"),
        ibg_host=ibg_host,
        ibg_port=ibg_port,
        ibg_client_id=ibg_client_id,
        account_id=account_id,
        instrument_provider=instrument_provider,
    ),
    "IB_ACCOUNT_2": InteractiveBrokersExecClientConfig(
        venue=Venue("IB_ACCOUNT_2"),
        ibg_host=ibg_host,
        ibg_port=ibg_port,
        ibg_client_id=ibg_client_id,
        account_id=account_id,
        instrument_provider=instrument_provider,
    ),
},

It's somewhat similar in that both aim to configure multiple exec_clients.
The difference is that I'm doing it to set up multiple accounts, whereas the example is configuring different venues:
https://github.com/nautechsystems/nautilus_trader/blob/develop/examples/live/binance/binance_spot_and_futures_market_maker.py

[faysou]

Ok IB_VENUE is used as constant in nautilus, you would need to think of what to do so it works not only with this constant. You need to search for IB_VENUE or IB in the code base.

[sunlei]

@faysou Thank you.

I've already searched for IB_VENUE and identified the areas that need modification.

However, I haven't developed the specific trading logic yet, which is why I've set this PR as a draft. I'll make further adjustments based on the actual development progress.
Once I've confirmed everything is working fine in live trading, I'll update the status of the current PR.

[faysou]

Ok thank you