Add mock DB mode for UI screenshots and demos

[MaxGhenis]

Problem

Taking screenshots for the website/marketing requires mock data (fake contacts like "Sarah Chen"), but the live app's Google Messages connection immediately syncs real messages over any mock DB swap. This makes the process fragile and has caused issues (stuck processes, DB corruption, real data leaking into screenshots).

Proposed solution

Add a --mock or --demo flag to openmessage serve that:

1. Copies site/seed-demo.sql into a temporary DB (not the real one)
2. Disables the Google Messages sync connection so mock data persists
3. Serves the web UI from the temp DB on the normal port

This would allow one-shot screenshot workflows:

openmessage serve --demo &
sleep 2
screencapture -l <window_id> screenshot.png
kill %1

Current workaround

Use existing pre-captured mock screenshots (site/screenshot-light.png etc.) and composite them with Pillow. Works but is brittle and doesn't capture the real macOS window chrome.

Files involved

• site/seed-demo.sql — existing mock data seed
• internal/app/app.go — data dir resolution
• cmd/serve.go — serve command entry point

[MaxGhenis]

This is now implemented on .

OpenMessage now supports both:

• (or )

That path:

• uses an isolated temporary data directory instead of your real store
• seeds fake SMS + WhatsApp conversations for screenshots and recordings
• disables live Google Messages, WhatsApp, and local desktop import sync

I also added binary-level coverage to prove demo mode serves seeded fake data without touching the configured real data dir.

If you still want this to load a checked-in SQL fixture like specifically, or you hit any rough edges in the screenshot workflow, feel free to reopen.

[MaxGhenis]

Clarifying the close note:

This is now implemented on main.

OpenMessage now supports both:

• openmessage demo
• openmessage serve --demo (or --mock)

That path:

• uses an isolated temporary data directory instead of your real store
• seeds fake SMS + WhatsApp conversations for screenshots and recordings
• disables live Google Messages, WhatsApp, and local desktop import sync

I also added binary-level coverage to prove demo mode serves seeded fake data without touching the configured real data dir.

If you still want this to load a checked-in SQL fixture like site/seed-demo.sql specifically, or you hit any rough edges in the screenshot workflow, feel free to reopen.