migrate-to-sent

Plans and executes a migration from Twilio, Sinch, Infobip, Vonage, or MessageBird/Bird to Sent v3 — mapping send calls, status vocabularies, webhook signature schemes, opt-out stores, templates, and tenancy models, then cutting over safely with dual-run and rollback. Use when replacing an incumbent CPaaS provider, translating provider code or webhook handlers to Sent, or planning a phased cutover and its verification gates.