Introduce sdy func manual axes.

To be attached to funcs and then for the shardy unflattener to use them. It is to prepare pushing shardy unflattener up past shard map export.

PiperOrigin-RevId: 905546069

Author: ekayaaslan

shardy/dialect/sdy/ir/constants.h

@@ -86,6 +86,9 @@ inline const std::string kEmptyMeshSymbol = "empty_mesh";
 // Attribute name for the original name of the func before flattening.
 inline constexpr llvm::StringRef kOriginalFuncName = "sdy.original_func_name";
 
+// Attribute name for the manual axes on the func.
+inline constexpr llvm::StringRef kFuncManualAxes = "sdy.func_manual_axes";
+
 // Attribute name of the main func.
 inline constexpr llvm::StringRef kMainFuncName = "main";