printedparts stage 6: RBAC - declared permissions gate every mutation

get_permissions declares view/create/edit/delete/restock (seeded on
install/enable and by flask seed permissions); every write route adds
require_permission on top of jwt_required. New test proves
authentication alone is not authorization: a role-less member gets
403 where an admin succeeds.

plugins/printedparts/plugin.py

@@ -51,6 +51,17 @@ class PrintedpartsPlugin(BasePlugin):
     def init_app(self, app: Flask, db_instance) -> None:
         logger.info(f'Printedparts plugin initialized (v{self.meta.version})')
 
+    def get_permissions(self) -> List:
+        """RBAC permissions this plugin owns (seeded on install/enable)."""
+        return [
+            ('printedparts.view', 'View 3D printed parts', 'printedparts'),
+            ('printedparts.create', 'Create printed parts', 'printedparts'),
+            ('printedparts.edit', 'Edit printed parts', 'printedparts'),
+            ('printedparts.delete', 'Retire printed parts', 'printedparts'),
+            ('printedparts.restock', 'Restock and adjust stock counts',
+             'printedparts'),
+        ]
+
     def get_navigation_items(self) -> List[dict]:
         return [
             {