Fix CoreML reshape to support dynamic shapes

CoreML MIL supports -1 in shape dimensions and can infer at runtime.
Change GetStaticShape to GetShape to allow dynamic input shapes,
and only apply ReshapeHelper when the shape is fully static.

Fixes #26328

Author: ingyukoh

onnxruntime/core/providers/coreml/builders/impl/reshape_op_builder.cc

@@ -40,15 +40,19 @@ Status ReshapeOpBuilder::AddToModelBuilderImpl(ModelBuilder& model_builder,
                                                const logging::Logger& logger) const {
   const auto& input_defs = node.InputDefs();
   std::vector<int64_t> input_shape;
-  ORT_RETURN_IF_NOT(GetStaticShape(*input_defs[0], input_shape, logger), "Cannot get shape of data");
+  ORT_RETURN_IF_NOT(GetShape(*input_defs[0], input_shape, logger), "Cannot get shape of data");
 
   const auto& data_name = input_defs[0]->Name();
   const auto& new_shape_name = input_defs[1]->Name();
   Initializer unpacked_tensor(model_builder.GetGraphViewer().GetGraph(), *model_builder.GetConstantInitializer(new_shape_name));
   TensorShapeVector new_shape = ToShapeVector(unpacked_tensor.DataAsSpan<int64_t>());
 
-  // ReshapeHelper applies the ONNX rules to create the concrete output shape
-  ReshapeHelper helper(TensorShape(input_shape), new_shape);
+  // ReshapeHelper applies the ONNX rules to create the concrete output shape.
+  // Only use it if the input shape is static (no dynamic dimensions).
+  // CoreML MIL supports -1 in the shape and can infer at runtime.
+  if (IsStaticShape(input_shape)) {
+    ReshapeHelper helper(TensorShape(input_shape), new_shape);
+  }
 
   if (model_builder.CreateMLProgram()) {
     using namespace CoreML::Specification::MILSpec;
@@ -96,7 +100,7 @@ bool ReshapeOpBuilder::IsOpSupportedImpl(const Node& node,
   }
 
   std::vector<int64_t> input_shape;
-  if (!GetStaticShape(*input_defs[0], input_shape, logger))
+  if (!GetShape(*input_defs[0], input_shape, logger))
     return false;
 
   if (input_shape.empty()) {