fix(release): stabilize dev build packaging

[drew]

Summary

Stabilize rolling dev build artifact publishing so dev releases use one computed version identity, predictable package aliases, and stale managed assets are pruned before upload.

Related Issue

None.

Changes

• Compute Python, Cargo, Debian, and RPM dev versions once from semantic tags and share that identity across release jobs.
• Normalize dev package filenames for Debian and RPM artifacts before publishing.
• Harden Packit RPM builds so local and workflow builds avoid non-semver operational tags and collect artifacts from Packit output paths.
• Move macOS cross-build Dockerfiles away from Docker Hub base images to reduce rate-limit failures.
• Add release tooling tests and update build architecture notes.

Testing

• mise run pre-commit passes
• Unit tests added/updated
• E2E tests passed in Release Dev workflow run 25455561827
• release-dev.yml workflow_dispatch succeeded: https://github.com/NVIDIA/OpenShell/actions/runs/25455561827
• Inspected dev release assets after publish; 23 assets with stable deb/rpm aliases and current wheels only

Checklist

• Follows Conventional Commits
• Commits are signed off (DCO)
• Architecture docs updated (if applicable)

[github-actions]

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