Upgrade Spack to v1.1.0

[wdconinc]

Briefly, what does this PR introduce?

Needs:

• Remove '%clang' requirement from several ACTS users #44

This PR upgrades spack to v1.1.0, https://github.com/spack/spack/releases/tag/v1.1.0.

What kind of change does this PR introduce?

• Bug fix (issue #__)
• New feature (issue #__)
• Documentation update
• Other: __

Please check if this PR fulfills the following:

• Tests for the changes have been added
• Documentation has been added / updated
• Changes have been communicated to collaborators

Does this PR introduce breaking changes? What changes might users need to make to their code?

No.

Does this PR change default behavior?

No.

[Copilot]

Pull Request Overview

This PR upgrades the Spack package manager version from v1.0.2 to v1.1.0 to incorporate the latest upstream changes and improvements from the Spack project.

• Updates the SPACK_VERSION variable to reference the v1.1.0 release
• Maintains existing cherry-picks for custom patches
• No breaking changes or behavior modifications

---

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[wdconinc]

Note to self:

There is a change in ordering of precedence between ~/.spack and $spack/etc/spack. We use this for user spack environments...

[wdconinc]

#20 79.36 ==> Added 2 new compilers to /opt/spack/etc/spack/site/packages.yaml
#20 79.36     llvm@19.1.7
#20 79.36     gcc@14.2.0
#20 79.36 ==> Compilers are defined in the following files:
#20 79.36     /opt/spack/etc/spack/site/packages.yaml
#20 85.66 ---  compilers: {}
#20 DONE 85.9s

https://github.com/eic/containers/actions/runs/19399309366/job/55504114628#step:14:2479