Fix uprating of cloned parameter subtrees

[MaxGhenis]

Summary

• Follow-up to Anthony's comment on Fix cache preservation and uprating order #491: Fix cache preservation and uprating order #491 (comment)
• Tracks uprating dependency sort traversal by parameter object identity so cloned subtrees with duplicate .name values are not skipped.
• Builds actual parameter paths from the root tree so cloned descendants resolve uprating metadata inside their current clone path when the dependency belonged to the cloned original prefix.
• Keeps root-scoped external dependencies root-scoped for reattached non-root clones, so clone-local parameter names do not silently shadow absolute upraters outside the cloned subtree.
• Avoids treating ordinary ParameterNodes with a child named brackets as scale objects during path traversal.
• Adds regressions for duplicate-name cloned subtrees, divergent baseline upraters after root mutation, reattached child-subtree clones preserving original parameter names, absolute external uprater paths inside reattached clones, and nodes with a brackets child name.

TDD / verification

• Confirmed the duplicate-name cloned-subtree regression failed before the first patch.
• Confirmed the divergent baseline-uprater regression failed before the scoped-resolution patch.
• Confirmed the reattached child-subtree clone regression failed before the original-to-current path mapping patch.
• Confirmed the external-root-uprater regression failed before limiting remaps to the original cloned prefix.
• Confirmed the brackets child-name regression matched the downstream policyengine-us CI failure before the path traversal fix.
• uv run --no-sync pytest tests/core/parameters/operations/test_uprating.py::test_parameter_uprating_processes_cloned_subtrees_with_duplicate_names -q
• uv run --no-sync pytest tests/core/parameters/operations/test_uprating.py::test_parameter_uprating_uses_cloned_subtree_upraters -q
• uv run --no-sync pytest tests/core/parameters/operations/test_uprating.py::test_parameter_uprating_uses_reattached_cloned_subtree_upraters -q
• uv run --no-sync pytest tests/core/parameters/operations/test_uprating.py::test_parameter_uprating_keeps_external_upraters_root_scoped_in_clones -q
• uv run --no-sync pytest tests/core/parameters/operations/test_uprating.py::test_parameter_uprating_handles_nodes_with_brackets_child_name -q
• uv run --no-sync pytest tests/core/parameters/operations/test_uprating.py -q
• uv run --no-sync ruff check policyengine_core/parameters/operations/uprate_parameters.py tests/core/parameters/operations/test_uprating.py
• uv run --no-sync ruff format --check policyengine_core/parameters/operations/uprate_parameters.py tests/core/parameters/operations/test_uprating.py
• uv run --no-sync --with policyengine-us --with policyengine-uk --with pytest-rerunfailures python -m pytest -m smoke --reruns 2 --reruns-delay 5 -v -s tests/smoke/test_country_init.py
• uv run --no-sync pytest -q