Rename enum values to avoid conflict with windows.h DELETE macro

[yuanmao1]

• Renamed DELETE to OP_DELETE in the Operation enum to avoid conflict with the DELETE macro defined in windows.h.
• Updated all references to the enum values to use the new names (e.g., OP_DELETE, OP_INSERT, OP_EQUAL).
• Ensured compatibility with existing code by making necessary adjustments where the enum was used.
  Operation enum conflict with windows.h DELETE macro #21