[Feature]: add extra packages for optional features

[zhongkechen]

What would you like?

I would like to have more optional features to be available in extra packages so that we can keep the core SDK package concise

Features will be available in the extra packages:

• virtual thread pool (requires Java 21+)
• [Design/RFC]: Support for annotation such as @Step #66 (performance penaties)
• [Feature]: parse SQSEvent and other trigger event types #366 (requires more dependencies)
• Add FileSystem serdes #463

Possible Implementation

No response

Is this a breaking change?

No

Does this require an RFC?

No

Additional Context

No response