Added file upload support

protocol/mizan-codegen/src/emit/rust.rs

@@ -440,5 +440,8 @@ fn rust_type_from_shape(shape: &TypeShape, ctx: &mut EnumCtx) -> String {
             // Value so the consumer can match on the runtime variant.
             "serde_json::Value".to_string()
         }
+        // The Rust adapter does not yet wire multipart; a file input surfaces
+        // as raw bytes until upload dispatch lands on this target.
+        TypeShape::Upload(_) => "Vec<u8>".to_string(),
     }
 }