Feature: Auto-select items tab for final stock locations (#11766) (#11955)

* Enhance: Auto-select items tab for final stock locations/categories

* Fix biome formatting in PanelGroup.tsx

* Change default setting to False per review

* Refactor: Rename setting to DISPLAY_ITEMS_FINAL_LEVEL to apply generically to both locations and categories per review

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Co-authored-by: Oliver <oliver.henry.walters@gmail.com>

src/backend/InvenTree/common/setting/user.py

@@ -268,4 +268,12 @@ USER_SETTINGS: dict[str, InvenTreeSettingsKeyType] = {
         'description': _('Save the last used printing machines for a user'),
         'default': '',
     },
+    'DISPLAY_ITEMS_FINAL_LEVEL': {
+        'name': _('Display Items at Final Level'),
+        'description': _(
+            'Automatically default to showing items/parts instead of sub-levels for locations or categories with no children'
+        ),
+        'default': False,
+        'validator': bool,
+    },
 }