Add containers 3.14 test with OCaml 5.3.0 compiler
Tests per-solution OCaml version support: containers.3.14 requires
ocaml < 5.4 and is solved with 5.3.0, verifying the worker loads the
correct compiler and stdlib without inconsistent assumptions errors.
Also updates universe hashes to match content-addressed output.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>