Skip deploy pipeline for version-bump commits

[anth-volk]

Fixes #208

Summary

• Skip the deploy pipeline root test job when a push head commit is exactly Update package version.
• Prevent downstream deploy, publish/deploy, and staging integration-test jobs from running on the versioning workflow commit.
• Preserve normal push deploys and manual workflow_dispatch deploys.

Verification

• YAML parsed successfully with Ruby YAML loader.
• actionlint unavailable locally.