PR #2571 fixed synth-E2E by branching MODEL_SLUG per runtime, but only
the langgraph branch was verified at runtime — hermes / claude-code /
override / fallback had zero automated coverage. A future regression
(e.g. dropping the langgraph case) would silently revert and only
surface as "Could not resolve authentication method" mid-E2E.
This PR:
- Extracts the dispatch into tests/e2e/lib/model_slug.sh as a sourceable
pick_model_slug() function. No behavior change.
- Adds tests/e2e/test_model_slug.sh — 9 assertions across all 5 dispatch
branches plus the override path. Verified to FAIL when any branch is
flipped (manually regressed langgraph slash-form to confirm the test
catches it; restored before commit).
- Wires the unit test into ci.yml's existing shellcheck job (only runs
when tests/e2e/ or scripts/ change). Pure-bash, no live infra.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
