Add Mistral Large 3 support. (#14213)

Co-authored-by: elvischenv <219235043+elvischenv@users.noreply.github.com>
Co-authored-by: Linda-Stadter <57756729+Linda-Stadter@users.noreply.github.com>

python/sglang/srt/configs/model_config.py

@@ -58,6 +58,8 @@ def is_deepseek_nsa(config: PretrainedConfig) -> bool:
             "DeepseekV3ForCausalLM",
             "DeepseekV32ForCausalLM",
             "DeepseekV3ForCausalLMNextN",
+            "MistralLarge3ForCausalLM",
+            "PixtralForConditionalGeneration",
         ]
         and getattr(config, "index_topk", None) is not None
     )
@@ -334,6 +336,8 @@ class ModelConfig:
             or "LongcatFlashForCausalLM" in self.hf_config.architectures
             or "LongcatFlashForCausalLMNextN" in self.hf_config.architectures
             or "DotsVLMForCausalLM" in self.hf_config.architectures
+            or "MistralLarge3ForCausalLM" in self.hf_config.architectures
+            or "PixtralForConditionalGeneration" in self.hf_config.architectures
         ):
             self.head_dim = 256
             self.attention_arch = AttentionArch.MLA
@@ -939,6 +943,7 @@ multimodal_model_archs = [
     "MultiModalityCausalLM",
     "MllamaForConditionalGeneration",
     "NemotronH_Nano_VL_V2",
+    "PixtralForConditionalGeneration",
     "Qwen2AudioForConditionalGeneration",
     "Qwen2VLForConditionalGeneration",
     "Qwen2_5_VLForConditionalGeneration",