TraderBot: Remove LoadOperationsFrom from config

https://github.com/linksplatform/Bot/blob/1d1f213febb4d9aab73eb647e83b2ec8478fe29a/csharp/TraderBot/appsettings.json#L27 - remove this setting from config and calculate it automatically.

For example, if we don't update this setting for too long we might get an error:



Start with csharp/TraderBot/appsettings.json at the referenced LoadOperationsFrom setting, then locate where that setting is read. Trace the surrounding TraderBot logic to determine how the value should be calculated automatically. Done means the configuration entry is removed and the bot no longer depends on manually updating it.

Written by the indexing model from the issue text.