[UI] BOM row expand (#11809)

* Add subassembly expansion

Co-authored-by: Copilot <copilot@github.com>

* Enable multi-level subassembly display

Co-authored-by: Copilot <copilot@github.com>

* Adjust padding

* Adds user setting to enable / disable subassembly view

Co-authored-by: Copilot <copilot@github.com>

* Add icon

* Additional playwright tests

Co-authored-by: Copilot <copilot@github.com>

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Co-authored-by: Copilot <copilot@github.com>

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

@@ -251,6 +251,12 @@ USER_SETTINGS: dict[str, InvenTreeSettingsKeyType] = {
         'default': False,
         'validator': bool,
     },
+    'SHOW_BOM_SUBASSEMBLY_LEVELS': {
+        'name': _('Show Subassemblies in BOM table'),
+        'description': _('Enable display of subassemblies in the BOM table'),
+        'default': True,
+        'validator': bool,
+    },
     'NOTIFICATION_ERROR_REPORT': {
         'name': _('Receive error reports'),
         'description': _('Receive notifications for system errors'),