fixture-add

name	fixture-add
description	Scaffold a new YAML test fixture and register its path constant in testutil/test_constants.go

The user provides: fixture type and content description.

Steps:

1. Choose the correct subdirectory under testdata/yaml-fixtures/:

   • GitHub Action → actions/javascript/, actions/composite/, or actions/docker/
   • Invalid/error case → actions/invalid/ or error-scenarios/
   • Config file → configs/
   • Dependency-heavy action → dependencies/

2. Create the YAML fixture file following the naming convention of existing fixtures in that directory. Inspect one existing fixture file first to match the YAML structure and formatting.

3. Add a constant to testutil/test_constants.go following the TestFixture<Name> pattern, pointing to the path relative to testdata/yaml-fixtures/ (e.g. "actions/composite/my-fixture.yml").

4. Run go build ./testutil/... to verify it compiles.

5. Show the user the usage pattern:

   testutil.WriteActionFixture(t, tmpDir, testutil.TestFixture<Name>)
   // or for config fixtures:
   testutil.MustReadFixture(testutil.TestFixture<Name>)