Excel Button Row Sync Macro

I maintain a multi-sheet employee workbook and need a small VBA routine that runs from a button sitting in every filled row. When the button is pressed, the code should:

• Copy the data from that exact row.
• Jump to my dedicated summary sheet.
• Search the key column for the same unique product code.
• If the code is present, overwrite the existing row with the new values; if it is not, append the data as a fresh row directly beneath the last entry.

The trigger must be the button click only—no automatic or manual menus elsewhere. The matching logic has to rely exclusively on that unique product code so nothing else changes the way duplicates are detected.

Deliverables
• A clean, well-commented VBA module tied to the button.
• Clear, brief notes on how to attach or replicate the button for any new rows I add later.
• Successful testing inside my current workbook, confirming both “update” and “create” behaviour work exactly as described.