fix(lint): resolve E505, E105, E410, E330 in ocaml-crypto
- Add 18 missing .mli interface files (pk/, rng/, src/)
- Fix E105: replace catch-all handler in gen_tables.ml
- Fix E410: simplify verify_z/verify doc args in dsa.mli
- Fix E330: rename chacha20_block to core_block
- Fix test_cipher.ml reference to non-existent octets_of_ctr