feat(constants): update model constants (#17)

* feat(Model)!: Update model constants

- Add new models Mistral Nemo and Codestral Mamba
- Add aliases to models constant to be deserialized seemlessly from the versioned forme (e.g.: "mistral-large-2407")
- The commonly named Mistral Large 2 is now `constants::Model::MistralLargeLatest` when the old one is `Model::MistralLarge`

* tests(Model): Update the tests to check the new model variants.

tests/v1_constants_test.rs

@@ -11,11 +11,14 @@ fn test_model_constant() {
         Model::OpenMistral7b,
         Model::OpenMixtral8x7b,
         Model::OpenMixtral8x22b,
+        Model::OpenMistralNemo,
         Model::MistralTiny,
         Model::MistralSmallLatest,
         Model::MistralMediumLatest,
         Model::MistralLargeLatest,
+        Model::MistralLarge,
         Model::CodestralLatest,
+        Model::CodestralMamba,
     ];
 
     let client = Client::new(None, None, None, None).unwrap();