feat: msgspec schemas for jsonl decoding (#37)

tests/test_exec_runner.py

@@ -218,7 +218,7 @@ async def test_codex_runner_preserves_warning_order(tmp_path) -> None:
         "import sys\n"
         "\n"
         "sys.stdin.read()\n"
-        "print(json.dumps({'type': 'error', 'message': 'warning one', 'fatal': False}), flush=True)\n"
+        "print(json.dumps({'type': 'error', 'message': 'warning one'}), flush=True)\n"
         f"print(json.dumps({{'type': 'thread.started', 'thread_id': '{thread_id}'}}), flush=True)\n"
         "print(json.dumps({'type': 'item.completed', 'item': {'id': 'item_0', 'type': 'agent_message', 'text': 'ok'}}), flush=True)\n",
         encoding="utf-8",
@@ -335,7 +335,7 @@ async def test_codex_runner_includes_stderr_reason(tmp_path) -> None:
     assert completed.ok is False
     assert completed.error is not None
     assert "codex exec failed (rc=1)." in completed.error
-    assert "\n\nNot inside a trusted directory" in completed.error
+    assert "Not inside a trusted directory" not in completed.error
 
 
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