Adds last_seen field to track when users last accessed the tool:
- Add lastSeen column to users table schema (nullable timestamp)
- Create migration to add last_seen column to existing databases
- Add updateLastSeen() function to auth.service.js
- Update auth derive middleware to update last_seen on each authenticated request (async, non-blocking)
- Add lastSeen to admin getUserStats() query for display in admin users table
- Add "Last Seen" column to admin users table in frontend
Co-Authored-By: Claude <noreply@anthropic.com>
Joerg
d1e4c39ad6
