feat(bx): wire advance/reimburse withdraw API clients

Co-authored-by: Cursor <cursoragent@cursor.com>

web-admin/src/api/bx/index.ts

@@ -114,6 +114,9 @@ export const advanceApi = {
   submit(id: BxId) {
     return bxRequest.post(`/advances/${id}/submit`)
   },
+  withdraw(id: BxId) {
+    return bxRequest.post(`/advances/${id}/withdraw`)
+  },
   approve(id: BxId, data: { approvalOpinion?: string }) {
     return bxRequest.post(`/advances/${id}/approve`, data)
   },