test(ci): enforce workflow name matches its file

AGENTS.md

@@ -59,11 +59,12 @@ Two keys, and the difference matters:
   the filename, so `pr-title / conventional title` names both the file to open
   and what it did. A matrix job's `name:` has to interpolate the matrix value
   (`pytest ${{ matrix.python-version }}`) or all three legs produce checks
-  called the same thing. `atdr/contrail-gh` enforces this in CI; here it is
-  convention. The `Analyze (python)` and `Analyze (actions)` checks are the
-  exception and always will be: CodeQL runs from default setup, which is a repo
-  setting rather than a file, so its name and its timeout are GitHub's to
-  choose.
+  called the same thing. `tests/test_workflow_naming.py` enforces this, the
+  same guard `atdr/contrail-gh#7` added as a shell step in CI there because
+  that repo has no test suite to hold it instead. The `Analyze (python)` and
+  `Analyze (actions)` checks are the exception and always will be: CodeQL runs
+  from default setup, which is a repo setting rather than a file, so its name
+  and its timeout are GitHub's to choose.
 - **Every job that can carry `timeout-minutes` sets one.** GitHub's default is
   six hours, and the failure that matters is a stall rather than an error: a
   `pip` or `npx` fetch that hangs never fails on its own. Ten minutes

tests/test_workflow_naming.py

@@ -0,0 +1,34 @@
+"""Every workflow's top-level `name:` must equal its own filename.
+
+GitHub labels a check `<workflow name> / <job name>` and never shows the
+filename, so a workflow named for what it does leaves a reader guessing which
+file under `.github/workflows/` produced a given check. Keeping the name equal
+to the filename makes that mapping mechanical; the description goes on the
+job instead. See atdr/contrail-gh#7, which added the same guard as a shell
+step because that repo has no test suite to host it in — contrail does, so it
+belongs here instead of prose in AGENTS.md that a change can silently ignore.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import yaml
+
+WORKFLOW_DIR = Path(__file__).parent.parent / ".github" / "workflows"
+WORKFLOW_PATHS = sorted(WORKFLOW_DIR.glob("*.yml")) + sorted(WORKFLOW_DIR.glob("*.yaml"))
+
+
+def test_there_are_workflows_to_check():
+    """A guard reading the wrong directory would otherwise pass by finding nothing."""
+    assert WORKFLOW_PATHS, f"no workflow files found under {WORKFLOW_DIR}"
+
+
+def test_every_workflow_is_named_after_its_file():
+    for path in WORKFLOW_PATHS:
+        stem = path.stem
+        name = yaml.safe_load(path.read_text()).get("name")
+        assert name == stem, (
+            f"{path.name} is named {name!r} but its checks should read {stem!r} "
+            "so a reader can tell which file produced them"
+        )