This update adds database indexes that help Odoo find related partner and purchase information more quickly. Business users should see improved responsiveness when opening or using partner records, especially in databases with many partners or purchase orders.

Adding some missing indexes:
- `res.partner.company_registry`: necessary for the second search in `_compute_same_vat_partner_id`
- `purchase.order.partner_id`: necessary for the `_read_group` in `res.partner._compute_purchase_order_count`

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This update adjusts internal performance test expectations for the Knowledge app after a backend caching behavior change. It helps keep automated checks accurate without changing the user-facing product experience.

Adapting query count, due to not putting html fields in cache upon creation.

task-4962646