fix(issue-23-24): merge review - the environment form of the auto-trust switch reaches the handler; a rate-limited dialog does not hide the next one

Two probes from the merge-side codex review (its report was lost to an API
outage; the probes and their results were recovered from its transcript):

- create_session.sh and resume_session.sh set AUTO_TRUST=1 and then
  exported MAM_AUTO_TRUST from it, so the documented MAM_AUTO_TRUST=0
  without a flag reached handle_startup_dialogs as 1: the operator had
  turned automatic trust off and it stayed on. Now AUTO_TRUST defaults to
  the environment value and an explicit --auto-trust/--no-auto-trust wins.
- _mam_dialog_pick exited on the first dialog inside its resend cooldown
  instead of looking further down the screen, so a skipped (--no-auto-trust)
  or just-answered trust prompt hid the codex update notice below it, which
  the docs say is always answered. It continues to the next dialog now; S5
  and S5b (one send per cooldown, one retry after it) still hold.

Regressions: S6c, S5f (startup path), R3b and C3 (resume/create, env only,
flag over env). Each fails without the fix. The create skill doc names the
environment form and its precedence.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VCgu9Fa9iT7TbJUSzdq4Ff

tests/test_issue24_resume_dialogs.py

@@ -100,6 +100,45 @@ def test_r3_no_auto_trust_reaches_the_dialog_handler(mam_sandbox, mock_herdr, mo
     assert _calls(log) == ["sess=test-r3-codex timeout=20 agent=codex auto_trust=0"]
 
 
+@pytest.mark.parametrize("env_value,flag,expected", [
+    ("0", (), "0"),               # the documented environment form alone
+    ("0", ("--auto-trust",), "1"),  # an explicit flag wins over the environment
+    ("1", ("--no-auto-trust",), "0"),
+])
+def test_r3b_the_environment_form_of_the_switch_reaches_the_handler_on_resume(
+        mam_sandbox, mock_herdr, mock_agents, monkeypatch, env_value, flag, expected):
+    """R3b (merge review, codex probe): MAM_AUTO_TRUST=0 without a flag used to
+    be overwritten by the script's own export of its default."""
+    tmp_path = mam_sandbox
+    ws = _create_and_stop(tmp_path, "codex", "test-r3b-codex")
+    log = _record_dialog_calls(tmp_path)
+    monkeypatch.setenv("MAM_AUTO_TRUST", env_value)
+    res = _resume(tmp_path, "codex", "test-r3b-codex", ws, extra=flag)
+    assert res.returncode == 0, res.stdout + res.stderr
+    assert _calls(log) == ["sess=test-r3b-codex timeout=20 agent=codex auto_trust=%s" % expected]
+
+
+@pytest.mark.parametrize("env_value,flag,expected", [
+    ("0", (), "0"),
+    ("0", ("--auto-trust",), "1"),
+    ("1", ("--no-auto-trust",), "0"),
+])
+def test_c3_the_environment_form_of_the_switch_reaches_the_handler_on_create(
+        mam_sandbox, mock_herdr, mock_agents, monkeypatch, env_value, flag, expected):
+    """C3 (merge review, codex probe): the same contract on create_session."""
+    tmp_path = mam_sandbox
+    log = _record_dialog_calls(tmp_path)
+    ws = str(tmp_path / "ws_c3")
+    os.makedirs(ws, exist_ok=True)
+    create = _script(tmp_path, SCRIPTS[0])
+    monkeypatch.setenv("MAM_AUTO_TRUST", env_value)
+    res = subprocess.run(["bash", create, "--workspace", ws, "--agent", "codex",
+                          "--role", "creator", "--session", "test-c3-codex", "--no-onboard", *flag],
+                         cwd=str(tmp_path), capture_output=True, text=True)
+    assert res.returncode == 0, res.stdout + res.stderr
+    assert _calls(log) == ["sess=test-c3-codex timeout=15 agent=codex auto_trust=%s" % expected]
+
+
 def test_r4_the_shipped_handler_really_runs_for_a_non_claude_resume(
         mam_sandbox, mock_herdr, mock_agents):
     """R4 (no override): with the real handle_startup_dialogs, a codex resume