Add Algorithm module to SDLS, ROCF service to SLE, convolutional/LDPC/turbo coding to tm-sync, station contacts to SGP4 GMAT interop, FlexACM package

- ocaml-sdls: Add Algorithm module for SA algorithm negotiation, re-export
- ocaml-sle: Add ROCF (Return Operational Control Field) service module
- ocaml-tm-sync: Add convolutional coding (rate 1/2 K=7), LDPC, turbo codes
with encode/decode and comprehensive unit tests
- ocaml-sgp4: Update GMAT interop station contacts test
- ocaml-hkdf: Regenerate opam with alcotest dep
- ocaml-flexacm: New package for flexible adaptive coding and modulation