Copying a Python tuple shares mutable field storage

### Feature Summary

Constructing a `Tuple` from another `Tuple` reuses the same internal ordered dictionary. Assigning a field on either tuple therefore changes the other tuple as well. An operator that creates and edits a derived tuple can silently mutate its input row.

Before: copied tuples share field storage and leak assignments in both directions.

Expected: a tuple copy starts with the same fields but has independent field mapping storage.

Reproduction evidence:

1. Create `original = Tuple({"x": 1})`.
2. Create `copied = Tuple(original)`.
3. Assign `copied["x"] = 2` and observe that `original["x"]` also becomes 2.

Version and commit evidence:

1.3.0-incubating-SNAPSHOT on main

**Commit Hash (Optional)**
50321e403c82df299a13deb50a7f9849dd93bdba

**Relevant log output**

original_x=2 derived_x=2 same_storage=True

### Proposed Solution or Design

Expected: a tuple copy starts with the same fields but has independent field mapping storage.

### Affected Area

Workflow Engine (Amber)