[feat] Add support for tools call

[BearBiscuit05]

Add support for tools call #344.

[BearBiscuit05]

An immature implementation has been completed using main_generation for initial testing. Currently, there are several design issues that need to be addressed:

1. The placement of the tool parameter is unclear.
2. When using chat to eventually call the generate_sequences function, should we create a new function for chat or directly reuse generate_sequences and use parameters to switch between self.rollout.chat and self.rollout.generate_sequences?
3. It’s uncertain whether the way the chat function is structured in the rollout class is concise enough.

In summary, I might need more time to streamline the params and gain a deeper understanding of verl. This will likely take some time. And I would appreciate some advice on this.

[CLAassistant]

All committers have signed the CLA.