Verify von Prelude migrieren

I am moving a phone verification integration from Prelude to Bird Verify. Route through it with me.
1. Check what you already have before setting anything up. If Bird's MCP server is connected, use its tools. If the Bird CLI is installed and signed in, use that. Either one is enough, and every step below is an action you take with whichever you have. Only if neither is present, follow https://bird.com/docs/ai/set-up-your-agent.md to set one up and sign me in. Every Bird docs page serves Markdown at its own URL with `.md` appended, so fetch that rather than the HTML.
2. Read https://bird.com/docs/guides/verify/migrate/prelude.md for the create, check and status mapping, and https://bird.com/docs/guides/verify/migrate.md for the order the steps go in.
3. Find and list my Prelude usage in this repository before you change anything: the /v2/verification and /v2/verification/check call sites, anywhere I read signals or a routing verdict, and anywhere I use dispatch_id for retry safety.
4. Tell me early which of these I depend on. Bird Verify has no voice channel and no silent or network-based authentication. It generates the code itself and never returns it, so I cannot supply my own. It accepts `options.language` but no per-request template or message body. Bird can use an existing SMS Sender ID or a connected WhatsApp number with an approved authentication template, configured per channel or country rather than per request; tell me whether my current sender can be kept. Prelude's risk layer does not port either: its signals, its routing verdicts and its silent verification have no counterpart in Bird Verify, so tell me every decision my code makes on those.
5. Configure my channels and destinations following https://bird.com/docs/guides/verify/countries.md and https://bird.com/docs/guides/verify/senders.md. While you are there, disable every country I do not actually verify into. An enabled destination I never send to is not reach, it is exposure to SMS pumping, so ask me which countries I serve rather than leaving the defaults.
6. Port the create and check calls using the mapping tables on the provider page, and move my status handling to Bird's events: https://bird.com/docs/guides/verify/sending-verifications.md and https://bird.com/docs/guides/verify/events.md.
7. Cut over at the create call, not all at once, because a code issued by Prelude cannot be checked by Bird and a code issued by Bird cannot be checked by Prelude. From the moment I say go, send every NEW verification to Bird, and keep routing each check to whichever provider issued that verification. Keep both paths live for one full code lifetime plus margin, then retire the old one. Tell me how you will decide which provider issued a given verification before you write any of it.
8. Test before any real traffic. Bird Verify has no simulated recipients, so do not look for a sandbox: the thing worth testing is the code arriving. Run the integration against a phone number and a mailbox I control, on each channel I enabled, and show me what arrived on each one.
9. Stop and ask me wherever a step needs a decision. Do not start routing new verifications to Bird until I have seen those test results and replied with the words cut over to Bird. Retiring the Prelude path is a separate step: ask me again and wait for me to reply with the words retire the Prelude path, and do not retire it while any code it issued could still be checked. A reply that agrees without naming what it is authorising is not authorisation. Finish by telling me what is left that only a person can do.