chore(theme): astro 锁定 ~5.18.0（终审 Minor）+ docs: Plan 4 收官

Co-Authored-By: Claude Code <noreply@anthropic.com>

.deps_siteforge_v812/_pytest/tracemalloc.py

@@ -0,0 +1,24 @@
+from __future__ import annotations
+
+
+def tracemalloc_message(source: object) -> str:
+    if source is None:
+        return ""
+
+    try:
+        import tracemalloc
+    except ImportError:
+        return ""
+
+    tb = tracemalloc.get_object_traceback(source)
+    if tb is not None:
+        formatted_tb = "\n".join(tb.format())
+        # Use a leading new line to better separate the (large) output
+        # from the traceback to the previous warning text.
+        return f"\nObject allocated at:\n{formatted_tb}"
+    # No need for a leading new line.
+    url = "https://docs.pytest.org/en/stable/how-to/capture-warnings.html#resource-warnings"
+    return (
+        "Enable tracemalloc to get traceback where the object was allocated.\n"
+        f"See {url} for more info."
+    )