Rust port of OmniVox, wire-compatible with the C++ original

Byte-exact cereal binary layout, RFC 8439 ChaCha20-Poly1305, RFC 7914
scrypt defaults; tokio transport preserving the original's observable
behavior (contract B1-B3, B5 quirks included). Parity evidence: golden
C++ vectors in tests/vectors.rs and loopback behavior tests; both
cross-directions verified against the unmodified C++ binaries.

Source: https://git.0xfeedc0de.com/michael/OmniVox

.gitignore

@@ -0,0 +1,3 @@
+/target
+**/*.rs.bk
+/opencode