Exercise emergency routing through the Codex adapter

Why: Parser hardening requires the emergency fixture to use the real Codex adapter contract instead of a custom adapter.

Evidence: Agent-exec and config suites pass 58 executions with one opt-in probe skipped; validate and diff-check pass.

Impact: Test fixture only; production validation remains strict.

Refs: feature/agent-cli-enforcement

tests/test_agent_exec.py

@@ -185,6 +185,12 @@ def _write_fake_worker(
     return path
 
 
+def _codex_help() -> str:
+    from scripts.agent_exec_adapters import _REQUIRED_HELP_MARKERS
+
+    return "\n".join(_REQUIRED_HELP_MARKERS["codex"]) + "\n"
+
+
 class AgentExecControllerTests(unittest.TestCase):
     def setUp(self) -> None:
         self.tmp = tempfile.TemporaryDirectory(prefix="agent-exec-ctrl-")
@@ -589,13 +595,27 @@ class AgentExecControllerTests(unittest.TestCase):
         _write_fake_worker(
             self.bindir,
             "codex",
+            help_text=_codex_help(),
             body=textwrap.dedent(
                 f"""\
+                if [ "$1" = "exec" ] && [ "$2" = "--help" ]; then
+                  exec "$0" --help
+                fi
                 printf 'codex\\n' >> "{launches}"
-                workspace="$1"
-                result="$3"
-                mkdir -p "$workspace/src"
-                printf 'final\\n' > "$workspace/src/marker.txt"
+                result=""
+                prev=""
+                for arg in "$@"; do
+                  if [ "$prev" = "--output-last-message" ]; then
+                    result="$arg"
+                  fi
+                  prev="$arg"
+                done
+                if [ -z "$result" ]; then
+                  echo "missing --output-last-message" >&2
+                  exit 2
+                fi
+                mkdir -p src
+                printf 'final\\n' > src/marker.txt
                 printf '%s\\n' '{{"terminal_status":"completed","summary":"done","changed_files":["src/marker.txt"],"evidence":[],"scope_expansion":null}}' > "$result"
                 exit 0
                 """
@@ -604,7 +624,7 @@ class AgentExecControllerTests(unittest.TestCase):
         self._configure(
             profiles={
                 "regular": {"adapter": "custom", "executable": "regular"},
-                "codex": {"adapter": "custom", "executable": "codex"},
+                "codex": {"adapter": "codex", "executable": "codex", "model": "auto"},
             },
             role_order=["regular"],
             max_attempts_per_profile=3,
@@ -614,6 +634,7 @@ class AgentExecControllerTests(unittest.TestCase):
         self.assertEqual(loaded.execution.max_attempts_per_profile, 3)
         self.assertEqual(loaded.execution.emergency_profile, "codex")
         self.assertIn("codex", loaded.profiles)
+        self.assertEqual(loaded.profiles["codex"].adapter, "codex")
         for role_names in loaded.roles.values():
             self.assertNotIn("codex", role_names)
         unit = _write_unit(self.root / "unit.json")
@@ -655,6 +676,7 @@ class AgentExecControllerTests(unittest.TestCase):
             line for line in launches.read_text(encoding="utf-8").splitlines() if line
         ]
         self.assertEqual(observed, ["regular", "regular", "regular", "codex"])
+        self.assertEqual(data["attempts"][-1]["summary"], "done")
         self.assertEqual(proc.returncode, agent_exec.EXIT_SUCCESS, proc.stderr + proc.stdout)
         self._assert_canonical_untouched()