#73 DB Migration: Invitations Table

Create database migration for user invitations table. Migration File: engine/migrations/sql/XXX_invitations_table.sql Table: invitations Columns: - id: uuid primary key - tenant_id: varchar(100) - email: varchar(255) - role: varchar(50) - invited_by: uuid (foreign key to users) - token_hash: varchar(64) unique - status: varchar(20) (pending, accepted, expired, cancelled) - created_at: timestamp - expires_at: timestamp - accepted_at: timestamp - accepted_by_user_id: uuid - cancelled_at: timestamp - cancelled_by: uuid - message: text (optional personal message) - resent_count: int default 0 - last_resent_at: timestamp Indexes: - idx_invitations_tenant_status - idx_invitations_email - idx_invitations_token_hash - idx_invitations_expires_at Constraints: - Unique: (tenant_id, email) where status = 'pending' With ultra attention to details and correctness. Before closing: write comment summarizing implementation with screenshot.