feat(automation): add durable runner and signed approval recovery

automation/tests/fake_codex.py

@@ -0,0 +1,31 @@
+"""Subprocess protocol double, used only in a disposable test checkout. No model/network."""
+import json
+from pathlib import Path
+import subprocess
+import sys
+import time
+
+args = sys.argv[1:]
+if args[0] == 'exec':
+    prompt = sys.stdin.read()
+    if Path('simulate-interruption').exists():
+        sys.exit(17)
+    if Path('simulate-timeout').exists():
+        time.sleep(60)
+    if '--sandbox' not in args or args[args.index('--sandbox') + 1] != 'workspace-write':
+        sys.exit(18)
+    checkpoint = 'work'
+    Path('result.txt').write_text('subprocess worker output', encoding='utf-8')
+    Path('observed-prompt.txt').write_text(prompt, encoding='utf-8')
+    result = dict(outcome='complete', summary='synthetic subprocess', blockers=[], requestedApprovals=[], checkpoint=checkpoint)
+    Path(args[args.index('--output-last-message') + 1]).write_text(json.dumps(result), encoding='utf-8')
+    print(json.dumps(dict(type='thread.started', thread_id='synthetic-thread-id')))
+    print(json.dumps(dict(type='turn.completed')))
+elif args[0] == 'sandbox':
+    # Remove known sandbox switches; execute the real deterministic check in the disposable repo.
+    index = 1
+    while args[index] in ('-C', '-c'):
+        index += 2
+    sys.exit(subprocess.run(args[index:], cwd=Path.cwd()).returncode)
+else:
+    sys.exit(19)