Update frontend login page.jsx และ backend

mariadb/init/01_99_dms_data_v5_1_deploy_table_password_resets.sql

@@ -0,0 +1,31 @@
+-- 01_99_dms_data_v5_1_deploy_table_password_resets.sql
+-- Purpose: Table for password reset flow (forgot/reset password)
+-- Depends on: users
+
+SET NAMES utf8mb4;
+SET time_zone = '+00:00';
+
+-- ใช้ IF NOT EXISTS ป้องกันรันซ้ำ
+CREATE TABLE IF NOT EXISTS password_resets (
+  id           BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
+  user_id      BIGINT UNSIGNED NOT NULL,
+  token_hash   CHAR(64)        NOT NULL COMMENT 'SHA-256(hex) ของ token ดิบที่ส่งให้ผู้ใช้',
+  expires_at   DATETIME        NOT NULL,
+  used_at      DATETIME        NULL,
+  created_at   DATETIME        NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  PRIMARY KEY (id),
+  UNIQUE KEY uq_password_resets_token_hash (token_hash),
+  KEY idx_password_resets_user_id   (user_id),
+  KEY idx_password_resets_expires   (expires_at),
+  CONSTRAINT fk_password_resets_user
+    FOREIGN KEY (user_id) REFERENCES users(user_id)
+    ON DELETE CASCADE ON UPDATE RESTRICT
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+-- (ออปชัน) กำจัด token ที่หมดอายุอัตโนมัติด้วย EVENT (หากเปิด event_scheduler)
+-- CREATE EVENT IF NOT EXISTS ev_prune_password_resets
+--   ON SCHEDULE EVERY 1 DAY
+--   DO DELETE FROM password_resets WHERE (used_at IS NOT NULL) OR (expires_at < NOW());
+
+-- DOWN (rollback)
+-- DROP TABLE IF EXISTS password_resets;