#70 DB Migration: Users Table Enhancement

Create database migration for enhanced users table. Migration File: engine/migrations/sql/XXX_users_table_enhancement.sql New Columns: - status: varchar(20) (active, suspended, pending, deleted) - last_login_at: timestamp - last_login_ip: inet - failed_login_attempts: int default 0 - locked_until: timestamp - mfa_enabled: boolean default false - mfa_secret: text (encrypted) - created_by: uuid (foreign key to users) - updated_at: timestamp - deleted_at: timestamp (soft delete) - metadata: jsonb (flexible user attributes) Indexes: - idx_users_status - idx_users_email_tenant - idx_users_last_login With ultra attention to details and correctness. Before closing: write comment summarizing implementation with screenshot.