Automate Daily Sales CSV Sync

I receive daily sales reports as CSV files with standard column headers and want a simple way to keep a Google Sheet current.

Here’s what I’m after:

• A lightweight script—Google Apps Script or any quick-deploy option—that auto-imports the newest CSV each day and appends the data without creating duplicates.
• A fallback for manual updates, such as a custom menu or button in the sheet that lets me upload a CSV and trigger the same refresh logic.

Because every file shares the same structure, no complex mapping is needed; just read the headers and push the rows.

Deliverables
1. Working script linked to my Google Sheet.
2. Clear, step-by-step setup and usage notes so I can run or tweak it on my own.

If the solution runs reliably and stays easy to maintain, that’s success.