CAS Supplier - Service Changes (Enhanced SWS)

**User Story**
As a user of the Supplier Web Service (SWS) with CAS, SIMS needs to follow any changes made that impact the use of the API.
The SWS is implementing enhancements to their supplier web service around the Supplier Name and how Individual Suppliers are searched, created and how exceptions are reported back through the API.

**Acceptance Criteria**
- [ ] Manual Intervention is no longer required when students have a mononym (null GIVEN NAMES) and they can be searched/created through the regular flow
- [ ] Update `Create Supplier and Site` & `Create Site` calls:
- [ ] "SupplierName" field needs to be: [GIVEN NAMES] [LAST NAME]
- [ ] Handle new Exception Processing (EP) process [[NEED TO CHECK WITH FINANCE TEAM]]
- [ ] New pending requests?
- [ ] Question to CAS: How do we receive a response once it's processed?

[Individual Supplier Web Service Field Requirements (All Requests) - Apr 2025.pdf](https://api.zenhub.com/attachedFiles/eyJfcmFpbHMiOnsibWVzc2FnZSI6IkJBaHBBd0FhQ3c9PSIsImV4cCI6bnVsbCwicHVyIjoiYmxvYl9pZCJ9fQ==--2d085ca261cfa3f95d2e9396f5bb49b93bf055d1/Individual%20Supplier%20Web%20Service%20Field%20Requirements%20%28All%20Requests%29%20-%20Apr%202025.pdf)

Start by reviewing the acceptance criteria and the linked Individual Supplier Web Service Field Requirements PDF, then identify the existing CAS/SWS supplier integration entry points. Confirm the required mononym flow and SupplierName format, and resolve with the finance team and CAS how new Exception Processing requests and responses should work before implementation.

Written by the indexing model from the issue text.