claire ice shelf om3 version used for long model run and future warming experiments, for archival

[claireyung]

DO NOT MERGE

This draft PR is to (cleanly) make a new executable that includes downloadable metadata, as per the discussion here

The commit matches the OM3 executable used to run an OM3 panan ice shelf experiment, which is pr142-36

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🚀 The latest prerelease access-om3/pr276-1 at b3a6565 is here: #276 (comment) 🚀

[github-actions]

🚀 Attempted to deploy access-om3 Prerelease pr276-1 with commit b3a6565

🖥️ Gadi Deployment ✔️

Usage Instructions

access-om3, defined in spack.yaml, will be deployed to Gadi as:

• 2026.05.004 as a Release (when merged).
• pr276-1 as a Prerelease (during this PR).

This Prerelease is accessible on Gadi using:

module use /g/data/vk83/prerelease/modules
module load access-om3/pr276-1

When using the above modules, the binaries shall be on your $PATH.

For advanced users, this Prerelease is also accessible on Gadi via /g/data/vk83/prerelease/apps/spack/1.1/spack in the access-om3-pr276-1 environment.
Due to inode-saving measures, one will have to manually untar the environment metadata before environment activation with tar -xf .spack-env .spack-env.tar. It will require one to have write privileges.

Configuration Information

This Prerelease is deployed using:

• access-nri/spack on branch 1.1
• ACCESS-NRI/upstream-spack-packages version access/v1.1
• access-nri/access-spack-packages version 2026.09.005
• access-nri/spack-config version 2026.08.001

If the above was not what was expected, commit changes to the manifest in this PR, or propose changes to build-cds config/settings.json.