Add stateless support per MCP core documentation

[rtwite]

Feature Support: Stateless Session

1. Added new options for stateless feature. This will now set sessionIdGenerator=undefined per MCP documentation listed above.
2. Created helper functions to reduce code duplication
3. Updated Unit Tests
4. Ran Lint
5. The fork of this change and the change of the fastmcp package have been deployed to our orgs k8s clusters and confirmed resolved the 404 session not found errors for the load balancing to (n) pods.
6. Created issue #31 clone from FastMcp

This PR aims to fix FastMcp Stateless Support issue / question that was created. Will have a follow-up PR for this FastMCP issue.

Feel free to request any desired changes since I made some assumptions / decisions.

[punkpeye]

Thank you