model : support step3-vl-10b (#21287)

* feat: support step3-vl-10b

* use fused QKV && mapping tensor in tensor_mapping.py

* guard hardcoded params and drop crop metadata

* get understand_projector_stride from global config

* img_u8_resize_bilinear_to_f32 move in step3vl class

* Apply suggestions from code review

Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>

* fix the \r\n mess

* add width and heads to MmprojModel.set_gguf_parameters

---------

Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>

gguf-py/gguf/constants.py

@@ -506,6 +506,7 @@ class VISION_PROJECTOR_TYPE(IntEnum):
     GEMMA3N   = auto()
     GEMMA3    = auto()
     QWEN3VL   = auto()
+    STEP3VL   = auto()
     COGVLM    = auto()
 
 
@@ -987,6 +988,8 @@ VISION_PROJECTOR_TYPE_NAMES: dict[VISION_PROJECTOR_TYPE, str] = {
     VISION_PROJECTOR_TYPE.GLM_EDGE:  "adapter",
     VISION_PROJECTOR_TYPE.MERGER:    "qwen2vl_merger",
     VISION_PROJECTOR_TYPE.GEMMA3:    "gemma3",
+    VISION_PROJECTOR_TYPE.QWEN3VL:   "qwen3vl_merger",
+    VISION_PROJECTOR_TYPE.STEP3VL:   "step3vl",
 }
 
 TENSOR_NAMES: dict[MODEL_TENSOR, str] = {
@@ -4105,6 +4108,7 @@ class VisionProjectorType:
     QWEN2VL = "qwen2vl_merger"
     QWEN25VL = "qwen2.5vl_merger"
     QWEN3VL = "qwen3vl_merger"
+    STEP3VL = "step3vl"
     ULTRAVOX = "ultravox"
     INTERNVL = "internvl"
     QWEN2A = "qwen2a" # audio