Scheduled Gmail Data Sync to Google Sheets

# 03. Handle No Eligible Customers

**Purpose:** This path executes if the initial filter finds *no* customers meeting the win-back criteria during the daily check.
1.  **Set Status:** Sets a variable indicating no eligible customers were found (`system_log = NOT_FOUND`).
2.  **Log Status:** Records this 'NOT_FOUND' status along with the current timestamp in the 'SYSTEM_LOG' Google Sheet. This helps track when the daily workflow ran but had no one to process.