Update to latest Mistral AI API (v1.0.0)

- Replace closed Model enum with flexible string-based Model type
  with constructor methods for all current models (Mistral Large 3,
  Small 4, Magistral, Codestral, Devstral, Pixtral, Voxtral, etc.)
- Add new API endpoints: FIM completions, Files, Fine-tuning, Batch
  jobs, OCR, Audio transcription, Moderations/Classifications, and
  Agent completions (sync + async for all)
- Add new chat fields: frequency_penalty, presence_penalty, stop,
  n, parallel_tool_calls, reasoning_effort, min_tokens, json_schema
  response format
- Add embedding fields: output_dimension, output_dtype
- Tool parameters now accept raw JSON Schema (serde_json::Value)
  instead of limited enum types
- Add tool call IDs and Required tool choice variant
- Add DELETE HTTP method support and multipart file upload
- Bump thiserror to v2, add reqwest multipart feature
- Remove strum dependency (no longer needed)
- Update all tests and examples for new API

tests/v1_constants_test.rs

@@ -6,26 +6,19 @@ use mistralai_client::v1::{
 };
 
 #[test]
-fn test_model_constant() {
+fn test_model_constants() {
     let models = vec![
-        Model::OpenMistral7b,
-        Model::OpenMixtral8x7b,
-        Model::OpenMixtral8x22b,
-        Model::OpenMistralNemo,
-        Model::MistralTiny,
-        Model::MistralSmallLatest,
-        Model::MistralMediumLatest,
-        Model::MistralLargeLatest,
-        Model::MistralLarge,
-        Model::CodestralLatest,
-        Model::CodestralMamba,
+        Model::mistral_small_latest(),
+        Model::mistral_large_latest(),
+        Model::open_mistral_nemo(),
+        Model::codestral_latest(),
     ];
 
     let client = Client::new(None, None, None, None).unwrap();
 
     let messages = vec![ChatMessage::new_user_message("A number between 0 and 100?")];
     let options = ChatParams {
-        temperature: 0.0,
+        temperature: Some(0.0),
         random_seed: Some(42),
         ..Default::default()
     };