fix(agent): preload jiter native parser

tests/agent/test_jiter_preload.py

@@ -0,0 +1,25 @@
+from __future__ import annotations
+
+import importlib
+import sys
+
+from agent import jiter_preload
+
+
+def test_preload_jiter_native_extension_loads_sdk_parser_dependency():
+    assert jiter_preload.preload_jiter_native_extension() is True
+    assert "jiter.jiter" in sys.modules
+
+
+def test_preload_jiter_native_extension_is_best_effort(monkeypatch):
+    monkeypatch.setattr(jiter_preload, "_JITER_PRELOADED", False)
+
+    def _raise_missing(name: str):
+        assert name == "jiter.jiter"
+        raise ModuleNotFoundError(name)
+
+    monkeypatch.setattr(importlib, "import_module", _raise_missing)
+
+    assert jiter_preload.preload_jiter_native_extension() is False
+    assert jiter_preload._JITER_PRELOADED is False
+    assert isinstance(jiter_preload._JITER_PRELOAD_ERROR, ModuleNotFoundError)