ci: migrate all workflows to Namespace runners

[claude]

Requested by Phil Chmalts · Slack thread

Summary

Move every job in the 10 workflow files onto profile-labeled Namespace runners, replacing GitHub-hosted ubuntu-latest. This aligns seamapi/javascript with the runner convention already used in seamapi/seam-connect.

Before

All 10 workflow files were 100% on GitHub-hosted ubuntu-latest:

• _build.yml (build)
• _publish.yml (publish)
• automerge.yml (merge)
• check.yml (test matrix, lint, install matrix, typecheck)
• format.yml (commit)
• generate.yml (commit)
• prune.yml (branches)
• publish.yml (release)
• semantic-release.yml (semantic, release)
• version.yml (tag)

After

Each job is pinned to a Namespace namespace-profile-* label appropriate for the work it does:

Workflow	Job(s)	New runs-on
_build.yml	build (npm pack)	namespace-profile-codegen
_publish.yml	publish (npm publish)	namespace-profile-standard
automerge.yml	merge	namespace-profile-mini
check.yml	test (matrix)	namespace-profile-npm-test (via matrix.os)
check.yml	lint	namespace-profile-codegen
check.yml	install (matrix)	namespace-profile-codegen (via matrix.os)
check.yml	typecheck	namespace-profile-codegen
format.yml	commit	namespace-profile-mini
generate.yml	commit	namespace-profile-codegen
prune.yml	branches	'namespace-profile-mini' (quoting preserved)
publish.yml	release	namespace-profile-standard
semantic-release.yml	semantic, release	namespace-profile-standard
version.yml	tag	namespace-profile-mini

For check.yml, the test and install jobs still use runs-on: ${{ matrix.os }}. Their matrix os list (previously the single value ubuntu-latest, with a matching include: - os: ubuntu-latest, os_name: Linux) now carries the appropriate Namespace label, keeping the matrix shape intact.

Notes

• No RUNNER_OVERRIDE fallback. Labels are hard-coded per the request; there is no vars.RUNNER_OVERRIDE == 'github' && 'ubuntu-latest' || ... conditional. An outage would require a YAML revert, not flipping a repo variable.
• No caller passes a runs-on input override to the reusable workflows: _build.yml and _publish.yml do not declare a runs-on input, and their callers (publish.yml, check.yml, semantic-release.yml) invoke them with only artifact/registry inputs — so pinning the runner inside each reusable workflow is safe.

Test plan

• CI runs on this PR pick up the Namespace labels and all jobs (build, test matrix, lint, install matrix, typecheck) succeed
• Confirm the org has namespace-profile-mini, namespace-profile-codegen, namespace-profile-npm-test, and namespace-profile-standard runners available for this repo before marking ready-for-review
• Once green, verify a format.yml and generate.yml run on a pushed branch (they only fire on non-main pushes)
• Follow-up: on the next semantic-release / publish / version cycle, confirm the release path (semantic -> version -> publish) still functions end-to-end

🤖 Generated with Claude Code

https://claude.ai/code/session_015ZbCLvCAyCca1zguyCbHT5

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Generated by Claude Code