Fix e2e-install test failing on tag pushes

[jarugupj]

Summary

• The e2e-install job in the Test workflow runs on every push, tags included. On a tag push the checkout is a detached HEAD, so git rev-parse --abbrev-ref HEAD in scripts/e2e-install-test.sh returns the literal string HEAD instead of a ref name.
• That value is passed to install.sh as BRANCH, producing git clone --branch HEAD, which fails with fatal: Remote branch HEAD not found in upstream origin and aborts the job.
• Fix: prefer GITHUB_REF_NAME (the tag or branch GitHub provides), falling back to git rev-parse for local runs. A tag is a valid --branch argument to git clone, so the source build resolves correctly on release tags.

Not a new regression: the e2e-install job has failed with this same error on every tag whose Test run completed (v0.1.0 and v0.2.0). It went unnoticed because it runs in the Test workflow, separate from the release workflow that publishes the tag.

Validation

• bash -n scripts/e2e-install-test.sh

🤖 Generated with Claude Code

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Note

Low Risk
Single-line CI script change with no production runtime impact.

Overview
Fixes e2e-install failing on tag pushes when the workflow checks out a detached HEAD.

scripts/e2e-install-test.sh now sets BRANCH from GITHUB_REF_NAME when GitHub Actions provides it (tag or branch name), and only falls back to git rev-parse --abbrev-ref HEAD for local runs. Previously, detached tag checkouts produced BRANCH=HEAD, which made install.sh run git clone --branch HEAD and fail.

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