The client_ed25519 and parsec authentication plugins use public domain (CC0-1.0) ed25519 code by str4d (https://github.com/str4d/ed25519-java).
It is "ref10" java implementation from the SUPERCOP ed25519:

Upstream version: 0.3.0 (net.i2p.crypto:eddsa:0.3.0, the latest release), plus the only later
upstream change to the files kept here: Utils.hexToBytes() rejecting odd-length input
(commit ad02a7f). Upstream master e0ac357 (2019-08-04) contains no further change to these files.
Declared as a bundled component in the SBOM (.github/sbom/enrich.groovy); keep the version there
in sync with this file.

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MariaDB changes:
- doesn't register ed25519 to global java providers
- remove unused classes (EdDSAEngine, key classes, security provider)
