refactor(settings): lazily initialize manager

py/services/settings_manager.py

@@ -3,6 +3,7 @@ import json
 import os
 import logging
 from datetime import datetime, timezone
+from threading import Lock
 from typing import Any, Dict, Iterable, List, Mapping, Optional
 
 from ..utils.settings_paths import ensure_settings_file
@@ -688,4 +689,29 @@ class SettingsManager:
         
         return templates.get(model_type, '{base_model}/{first_tag}')
 
-settings = SettingsManager()
+
+_SETTINGS_MANAGER: Optional["SettingsManager"] = None
+_SETTINGS_MANAGER_LOCK = Lock()
+
+
+def get_settings_manager() -> "SettingsManager":
+    """Return the lazily initialised global :class:`SettingsManager`."""
+
+    global _SETTINGS_MANAGER
+    if _SETTINGS_MANAGER is None:
+        with _SETTINGS_MANAGER_LOCK:
+            if _SETTINGS_MANAGER is None:
+                _SETTINGS_MANAGER = SettingsManager()
+    return _SETTINGS_MANAGER
+
+
+def reset_settings_manager() -> None:
+    """Reset the cached settings manager instance.
+
+    Primarily intended for tests so they can configure the settings
+    directory before the manager touches the filesystem.
+    """
+
+    global _SETTINGS_MANAGER
+    with _SETTINGS_MANAGER_LOCK:
+        _SETTINGS_MANAGER = None