Add BLAKE3 hashing algorithm

This uses the single-threaded C-based routines from libblake3.

This is not optimal performance-wise but should be a good starting point
for nix compatibility with BLAKE3 hashing until a more performant
implementation based on the multi-threaded BLAKE3 routines
(written in Rust) can be developed.

src/libutil/package.nix

@@ -6,6 +6,7 @@
   boost,
   brotli,
   libarchive,
+  libblake3,
   libcpuid,
   libsodium,
   nlohmann_json,
@@ -42,6 +43,7 @@ mkMesonLibrary (finalAttrs: {
 
   buildInputs = [
     brotli
+    libblake3
     libsodium
     openssl
   ] ++ lib.optional stdenv.hostPlatform.isx86_64 libcpuid;