Support for conda repodata.json.zst format

Hi,

Nexus: 3.69.0-02
client micromamba v3.2.0

When using the conda proxy I’m not able the get the new conda metadata repo working downloaded.

#9 28.99 warning  libmamba Failed to load subdir: Transfer finalized, status: 404 [https://nexus.proxy.internal.com/repository/conda-proxy/main/linux-64/repodata.json.zst] 0 bytes