/health already returned GITHUB_SHA in its response but never logged
it, and the fastapi lambda's Terraform environment never actually set
GITHUB_SHA — so every health check response contained "unknown" in
production. Wire var.github_sha through the fastapi lambda module
(default "unknown" for local/other invocations) via a new
TF_VAR_github_sha env var set from `github.sha` in
_deploy_lambda.yml's Terraform Plan step, and log it on every /health
call so a request in CloudWatch can be tied back to the deploy that
served it.
Also fix the zip-size gate added for PR #1469: putting it in
tests/test_lambda_zip_size.py (run via the Docker-based ddd_tests.yml
suite) broke CI, because Dockerfile.test's build context excludes
deployment/* (.dockerignore), so check_lambda_zip_size.py couldn't
find variables.tf to read zip_excludes from inside that container.
Move the check to its own lightweight workflow,
check_lambda_zip_size.yml, triggered on pull_request into main — a
plain checkout (no Docker build) has the full repo, so the check
works, runs fast, and still gates merges to main before a regression
can roll into the dev deploy.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>