Refactoring adding psk method - #415

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(242) * Warning 242 at /home/runner/.cargo/git/checkouts/hax-580ebeee043cdea1/e7e54d0/hax-lib/proof-libs/fstar/rust_primitives/Rust_primitives.Hax.fst(136,0-136,81): - Definitions of inner let-rec while_loop_internal and its enclosing top-level letbinding are not encoded to the solver, you will only be able to reason with their types - Also see: /home/runner/.cargo/git/checkouts/hax-580ebeee043cdea1/e7e54d0/hax-lib/proof-libs/fstar/rust_primitives/Rust_primitives.Hax.fst(115,10-115,29)