fix: permissions matrix UI now returns proper shape from backend

The frontend admin.js expects {sets, users, permissions} but
ListPermissions returned a flat []SetPermission slice.

- Add PermissionsMatrix struct with JSON tags
- Update AdminService.ListPermissions to return *PermissionsMatrix
- Update mocks and all call sites to match new signature
- Update tests to assert the new matrix shape

1 files changed, 1 insertions, 1 deletions

diff --git a/internal/api/handlers_more_test.go b/internal/api/handlers_more_test.go
index 13c57cf..b162fa8 100644
--- a/internal/api/handlers_more_test.go
+++ b/internal/api/handlers_more_test.go
@@ -1583,7 +1583,7 @@ func TestServer_AdminListPermissions(t *testing.T) {
 			var as service.AdminService
 			if !tt.svcNil {
 				as = &service.MockAdminService{
-					ListPermissionsFunc: func(ctx context.Context) ([]model.SetPermission, error) { return nil, tt.svcErr },
+					ListPermissionsFunc: func(ctx context.Context) (*service.PermissionsMatrix, error) { return nil, tt.svcErr },
 				}
 			}
 			srv := newTestServer(t, store, nil, sm, cfg, nil, as, nil, nil)