Fix PR159 contract tests

[EricNGOntos]

Summary

• Align page-memory contract coverage with PR159 page and shard-page support.
• Update Excel parse contract assertions to check table asset metadata and pure HTML persisted content.

Test plan

• uv run pytest apps/worker/tests/contract/test_document_agent_budget_contract.py::test_page_memory_granularity_routes_supported_page_modes apps/worker/tests/contract/test_parse_task_contract.py::test_parse_task_should_process_uploaded_file_through_real_contract_boundaries -q
• uv run pytest apps/api/tests apps/worker/tests/contract -q

Made with Cursor