Add real RM approvers API and dedupe CCL field on WFH requests
- New GET /catalog/rm-approvers endpoint (mirrors ccl-approvers), backend controller + route, frontend service + RmApprover type
- WFH "Choose your RM" now lists real RM-role users instead of a hardcoded array
- WFH "Choose your CCL" now uses the real CclApprover data already fetched for the approval-matrix-driven cclApproverId field, and is hidden entirely when that field is already shown (avoids asking the requester to pick a CCL person twice on WFH requests needing CCL approval)