System Image Naming Conventions, Azure Agent Migration, and ZFS Import Behavior

13th chunk of `nixos/doc/manual/release-notes/rl-2505.section.md`

59e4bf892812b08ad13852ca071192cd0a7cd30397eeecca0000000100000fe1

- `virtualisation.azure.agent` option provided by `azure-agent.nix` is replaced by `services.waagent`, and will be removed in a future release.

- The ZFS import service now respects `fileSystems.*.options = [ "noauto" ];` and does not add that pool's import service to `zfs-import.target`, meaning it will not be automatically imported at boot.

- Default file names of images generated by several builders in `system.build` have been changed as outlined in the table below.

  Names are now known at evaluation time and customizable via the new options `image.baseName`, `image.extension`, `image.fileName` and `image.filePath` with the latter returning a path relative to the derivations out path (e.g. `iso/${image.fileName` for iso images).

  | `system.build` Option    | Old Filename                                               | New Filename                                                    |
  | ------------------------ | ---------------------------------------------------------- | ----------------------------------------------------------------|
  | amazonImage              | nixos-amazon-image-25.05pre-git-x86_64-linux.vhd           | nixos-image-amazon-25.05pre-git-x86_64-linux.vhd                |
  | azureImage               | disk.vhd                                                   | nixos-image-azure-25.05pre-git-x86_64-linux.vhd                 |
  | digitalOceanImage        | nixos.qcow2.gz                                             | nixos-image-digital-ocean-25.05pre-git-x86_64-linux.qcow2.gz    |
  | googleComputeImage       | nixos-image-25.05pre-git-x86_64-linux.raw.tar.gz           | nixos-image-google-compute-25.05pre-git-x86_64-linux.raw.tar.gz |
  | hypervImage              | nixos-25.05pre-git-x86_64-linux.vhdx                       | nixos-image-hyperv-25.05pre-git-x86_64-linux.vhdx               |
  | isoImage (installer)     | nixos-25.05pre-git-x86_64-linux.iso                        | nixos-image-25.05pre-git-x86_64-linux.iso                       |
  | isoImage                 | nixos.iso                                                  | nixos-image-25.05pre-git-x86_64-linux.iso                       |
  | kubevirtImage            | nixos.qcow2                                                | nixos-image-kubevirt-25.05pre-git-x86_64-linux.qcow2            |
  | linodeImage              | nixos-image-25.05pre-git-x86_64-linux.img.gz               | nixos-image-linode-25.05pre-git-x86_64-linux.img.gz             |
  | metadata (lxc-container) | nixos-system-x86_64-linux.tar.xz                           | nixos-image-lxc-metadata-25.05pre-git-x86_64-linux.tar.xz       |
  | OCIImage                 | nixos.qcow2                                                | nixos-image-oci-25.05pre-git-x86_64-linux.qcow2                 |
  | openstackImage (zfs)     | nixos-openstack-image-25.05pre-git-x86_64-linux.root.qcow2 | nixos-image-openstack-zfs-25.05pre-git-x86_64-linux.root.qcow2  |
  | openstackImage           | nixos.qcow2                                                | nixos-image-openstack-25.05pre-git-x86_64-linux.qcow2           |
  | sdImage                  | nixos-sd-image-25.05pre-git-x86_64-linux.img.zst           | nixos-image-sd-card-25.05pre-git-x86_64-linux.img.zst           |
  | tarball (lxc-container)  | nixos-system-x86_64-linux.tar.xz                           | nixos-image-lxc-25.05pre-git-x86_64-linux.tar.xz                |
  | tarball (proxmox-lxc)    | nixos-system-x86_64-linux.tar.xz                           | nixos-image-lxc-proxmox-25.05pre-git-x86_64-linux.tar.xz        |
  | vagrantVirtualbox        | nixos-25.05pre-git-x86_64-linux.ova                        | nixos-image-virtualbox-25.05pre-git-x86_64-linux.ova            |
  | virtualBoxOVA            | virtualbox-vagrant.box                                     | nixos-image-vagrant-virtualbox-25.05pre-git-x86_64-linux.ova    |
  | vmwareImage              | nixos-25.05pre-git-x86_64-linux.vmdk                       | nixos-image-vmware-25.05pre-git-x86_64-linux.vmdk               |

Title: System Image Naming Conventions, Azure Agent Migration, and ZFS Import Behavior

Summary

This document outlines several system changes, including the deprecation of `virtualisation.azure.agent` in favor of `services.waagent`. The ZFS import service now respects `fileSystems.*.options = [ "noauto" ];`, preventing specified pools from being automatically imported at boot. Furthermore, the default filenames for images generated by various `system.build` options have been updated for consistency. Users can now customize these filenames using new options such as `image.baseName`, `image.extension`, `image.fileName`, and `image.filePath`, which are known at evaluation time. A detailed table provides examples of old and new filenames across different image types like Amazon, Azure, DigitalOcean, ISOs, and various virtualization formats.