bug: list_data_products MCP tool calls list_products with unsupported domain/status kwargs (pre-existing)

Found during code review of PR #597 (multi-domain #520), but pre-existing on development — not introduced by that PR.

Bug

src/backend/src/tools/data_products.py (list_data_products tool, ~line 625):

products = ctx.data_products_manager.list_products(
    skip=0, limit=limit, domain=domain, status=status
)

But DataProductsManager.list_products signature is (skip, limit, project_id, is_admin, caller_email, caller_team_ids, caller_project_ids, include_history) — it accepts neither domain nor status. Any invocation of the tool raises TypeError: list_products() got an unexpected keyword argument 'domain'.

Verified present on origin/development (same call site + same param-less signature), so this is not a #520 regression.

Suggested fix

Either add domain/status filtering to list_products (domain would go through the entity_domain_associations junction now), or drop those kwargs from the tool call and filter in the tool. Out of scope for #597 to avoid scope creep.

Start in src/backend/src/tools/data_products.py around list_data_products and compare its list_products call with the DataProductsManager.list_products signature. Reproduce the tool invocation to confirm the unsupported-keyword TypeError, then determine whether filtering belongs in the manager or tool. Done means list_data_products no longer fails because of the domain/status arguments and its filtering behavior is defined.