Update and expand COTS computing HW cost models

1. Have more up to date and accurate projections of what the costs of systems are likely to be per array assembly.
2. Ensure that components common to product families are costed consistently.
3. Update risk registers according to findings.

KR1: updated costs for SDP costed concept for AA4 baseline

KR2: models for a few scenarios of architectural alternatives that will be investigated through co-design

KR3: Other COTS systems repriced ahead of CPF contract procurements