Add db-dump and db-migrate scripts to strip \restrict lines

PostgreSQL 17.6+ adds random \restrict/\unrestrict tokens to pg_dump
output (CVE-2025-8714 security fix), causing schema.sql to appear
changed on every dump even when the schema hasn't changed.

These wrapper scripts run dbmate and strip the \restrict lines from
the output to keep schema.sql stable.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

db/schema.sql

@@ -1,4 +1,3 @@
-\restrict F9AizESreuRieL4inRcHWWg3hyNET0FgnBDFBBBU3cZGPEpHjb591l8S2iglpap
 
 -- Dumped from database version 17.7
 -- Dumped by pg_dump version 17.7
@@ -1084,7 +1083,6 @@ ALTER TABLE ONLY public.user_devices
 -- PostgreSQL database dump complete
 --
 
-\unrestrict F9AizESreuRieL4inRcHWWg3hyNET0FgnBDFBBBU3cZGPEpHjb591l8S2iglpap
 
 
 --