feat: add migration for admin actions and role fields

Adds new tables and columns for admin functionality:

- Create admin_actions table for audit logging
- Create qso_changes table for sync job rollback support
- Add role column to users (default: 'user')
- Add is_admin column to users (default: false)

No data loss - uses ALTER TABLE with safe defaults.

Co-Authored-By: Claude <noreply@anthropic.com>

drizzle/meta/_journal.json

@@ -15,6 +15,13 @@
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