feat(topology): vacuum coordinate and multi block

Two major changes in this version. First stroid now embeds a vacuum coordinate as part of its StroidMesh file (this is a packed set of mfem meshes and GridFunction). This is a logical coordinate from 0 at the stellar surface to 1 at the mesh surface / compactified infinity which can be used by consumers to much more stablly infer position in the vacuum region. Second, there is a new topology backend, multi_block, which has been made the default. See the readme for more information but the basic jist is that multi_block addes 6 transition blocks onto the edge of the core domain. This allows for a much more well conditioned transition from the internal cartesien region to the external spherical region. The mesh conditioning improves by roughly a factor of 1000 for the same refinement level when compared to the legacy topology. The legacy topology is maintained as a option if core_mapping is set to spherified in the config.

meson.build

@@ -1,4 +1,4 @@
-project('stroid', 'cpp', meson_version : '>= 1.3.0', version : 'v0.4.0', default_options : ['cpp_std=c++23'])
+project('stroid', 'cpp', meson_version : '>= 1.3.0', version : 'v0.5.0', default_options : ['cpp_std=c++23'])
 
 subdir('build-check')
 
@@ -28,6 +28,7 @@ if get_option('pkg_config')
         ],
         subdirs: ['stroid'],
         filebase: 'stroid',
-        install_dir: join_paths(get_option('libdir'), 'pkgconfig')
+        install_dir: join_paths(get_option('libdir'), 'pkgconfig'),
+        requires: ['fourdst_config']
     )
 endif