Summary
- move the auto-enable RLS trigger SQL example from the event trigger
guide into the row-level-security guide with a full example
- keep a reference in the event trigger guide that points to the
row-level-security section instead of duplicating the SQL snippet
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## Summary by CodeRabbit
* **Documentation**
* Reorganized PostgreSQL Row Level Security documentation with a new
dedicated guide section on automatically enabling RLS for newly created
tables
* Note: Auto-enable RLS applies only to tables created after
installation; existing tables require manual enabling
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