Add multi-instrument rotation trading example with Controller

[graceyangfan]

Feature Request

Adding this example will help users expand their thinking by demonstrating how to manage and trade multiple instruments effectively. It provides a practical illustration of how to apply rotation strategies across different assets, making it easier for users to understand and implement advanced trading concepts.

[rterbush]

Saw this cross my desk a few months ago and was looking forward to exploring this. I see the PR was deleted @graceyangfan . Reason for that?

[graceyangfan]

@rterbush Unfortunately, the strategy automatically terminated after running for a while, without any obvious error messages. I currently don't have the time to investigate, but this approach is still worth exploring.