Why?:

• Adds a free source to the derivatives.options.chains endpoint with just the core providers.

What? (1-3 sentences or a bullet point list):

• obb.derivatives.options.chains(provider="yfinance")
• Key data related to the underlying symbol is returned to extra["results_metadata"]. This info can be used as inputs for Greeks calculations, among other things.

Impact:

• No changes to standard models or router components.

• Better data coverage out-of-the-box.

Testing Done:

• Unit/integration tests.

• obb.derivatives.options.chains("^SPX", provider="yfinance")