issue#6393 Fixed User unfriendly behavior of attributes.all when stored

[Karanveer266]

Summary of Changes

• Fixed Persistence Issue:
  Resolved an issue where modifications to the attribute dictionary returned by .all did not persist correctly for stored nodes.

• New Dictionary Wrapper - _AttributesDict:
  Introduced a custom dictionary wrapper that dynamically verifies a node’s is_stored status. If modifications are attempted on a stored node, a ModificationNotAllowed error is raised to prevent unintended changes.

• New get_dict() Method:
  Implemented a method that returns a deep copy of the node’s attributes, ensuring users must utilize proper setter methods (set(), etc.) for modifications instead of modifying attributes directly.

• Enhanced Documentation & Warnings:
  Updated documentation and warning messages on the .all property to guide users toward the correct API usage, reducing misuse and confusion.

• Backward Compatibility Maintained:
  Ensured compatibility with existing implementations while deprecating direct modifications through .all, providing a smooth transition for users.

Closes #6393