Google Sheets Scripted Dashboard Automation

I need my existing Google Sheets brought to life with App Script. The core worksheet already holds credentials for a hosted SQL database; what’s missing is the workflow that keeps everything updated and a set-and-forget visual dashboard.

Here’s the flow I want:

• A script that connects securely to the database, pulls fresh data on a schedule I can adjust (hourly to daily), and writes the results to the correct tabs without breaking existing formulas.
• Reverse export for two tables: when I flag a row as “ready”, the script should push that record back to the database in real time.
• Three custom functions—simple, callable like =GETSTATUS(), =NETMARGIN() and =LASTSYNC()—so daily users don’t touch the script editor.
• A clean, interactive dashboard inside the same file: slicers, progress bars, sparkline trends and conditional-format traffic lights. Everything should update automatically from the imported data.

Acceptance is straightforward: the scheduled import runs for a week without manual intervention; flagged records reach the database within a minute; all three custom functions return accurate results; and the dashboard refreshes as soon as new data hits.

Please build entirely in Google Apps Script and native Sheets features—no add-ons—to keep it maintenance-friendly. Let me know your approach and how fast you can turn the first draft around.