feat(usuarios): script para usar el correo del apoderado como login

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

scripts/actualizar_login_a_correo.sql

+BEGIN;
+
+CREATE TABLE IF NOT EXISTS intranet.users_login_backup_20261007 AS
+SELECT user_id, user_login, now() AS backed_up_at
+FROM intranet.users;
+
+CREATE TEMP TABLE login_candidates ON COMMIT DROP AS
+SELECT u.user_id,
+       lower(btrim(p.persona_correo)) AS email
+FROM intranet.users u
+         JOIN persona.pe_persona p ON p.persona_id = u.parent_id
+WHERE lower(btrim(p.persona_correo)) ~ '^[a-z0-9._%+-]+@[a-z0-9-]+(\.[a-z0-9-]+)*\.[a-z]{2,}$';
+
+CREATE TEMP TABLE login_updates ON COMMIT DROP AS
+SELECT c.user_id, c.email
+FROM login_candidates c
+WHERE c.email IN (SELECT email FROM login_candidates GROUP BY email HAVING count(*) = 1)
+  AND NOT EXISTS (SELECT 1
+                  FROM intranet.users o
+                  WHERE lower(o.user_login) = c.email
+                    AND o.user_id <> c.user_id)
+  AND NOT EXISTS (SELECT 1
+                  FROM intranet.users s
+                  WHERE s.user_id = c.user_id
+                    AND s.user_login = c.email);
+
+SELECT count(*) AS usuarios_a_actualizar FROM login_updates;
+
+UPDATE intranet.users u
+SET user_login = l.email
+FROM login_updates l
+WHERE u.user_id = l.user_id;
+
+SELECT count(*) AS logins_duplicados_tras_update
+FROM (SELECT lower(user_login) FROM intranet.users GROUP BY lower(user_login) HAVING count(*) > 1) d;
+
+COMMIT;