Update UK release bundle to policyengine-uk 2.88.23

[MaxGhenis]

Summary

• update the UK bundle to policyengine-uk 2.88.23 and policyengine-uk-data 1.55.12
• switch default UK managed datasets and docs from FRS 2023-24 to FRS 2024-25
• regenerate the UK release manifest and TRACE TRO against HF release commit 4e25f9d6b67244340161098e76bb5e67148eb1e7

Validation

• built and uploaded the policyengine-uk-data 1.55.12 HF release artifacts
• HUGGING_FACE_TOKEN=... uv run --extra dev python -m pytest tests/test_release_manifests.py tests/test_models.py tests/test_uk_regions.py -q

Notes

• HF release is finalized at policyengine/policyengine-uk-data-private tag 1.55.12, commit 4e25f9d6b67244340161098e76bb5e67148eb1e7
• the upload script completed HF upload, then failed on the GCS mirror with 403 because max@policyengine.org lacks storage.objects.create on policyengine-uk-data-private