Fix inlay hints for rest tuple tail

[ThanhNguyxn]

Fixes #59979

Summary

• map rest tuple tail arguments to the trailing required element labels in parameter hints
• keep existing hint behavior for non-rest and non-tuple rest parameters
• add fourslash baseline for rest tuple tail parameter hints

Testing

• npx hereby format
• npx hereby runtests --tests=tests/cases/fourslash/inlayHintsRestTupleTail.ts