C224 adjoint tests in jelf

CONTRIBUTORS.md

@@ -1,5 +1,4 @@
 # Contributors
-
 | GitHub user     | Real Name         | Affiliation | Date       |
 | --------------- | ----------------- | ----------- | ---------- |
 | james-bruten-mo | James Bruten      | Met Office  | 2025-12-09 |
@@ -11,3 +10,4 @@
 | harry-shepherd  | Harry Shepherd    | Met Office  | 2026-01-08 |
 | DrTVockerodtMO  | Terence Vockerodt | Met Office  | 2026-01-08 |
 | MetBenjaminWent | Benjamin Went     | Met Office  | 2026-01-15 |
+| tom-j-h         | Tom Hill          | Met Office  | 2026-01-16 |

applications/adjoint_tests/example/C12.nml → applications/adjoint_tests/example/C12_MG.nml

@@ -25,11 +25,12 @@
 !     respectively
 !===================================================================
 &mesh
-  mesh_file_prefix = 'mesh_C12'
+  mesh_file_prefix = 'mesh_C12_MG'
   geometry         = 'spherical'
   topology         = 'periodic'
-  n_meshes         = 1
-  mesh_names       = 'C12'
+  n_meshes         = 3
+  mesh_names       = 'dynamics','multigrid_l1','multigrid_l2'
+  mesh_maps        = 'dynamics:multigrid_l1','multigrid_l1:multigrid_l2'
   partition_mesh   = .false.
   coord_sys        = 'll'
   rotate_mesh      = .false.