从 Twilio 迁移 SMS

Help me migrate my SMS integration from Twilio to Bird.
1. Inspect this repository's sends, senders, callbacks, schedules, templates, opt-outs and tests. List the traffic and behavior that must survive the migration.
2. Read https://bird.com/docs/guides/sms/migrate/twilio.md and https://bird.com/docs/guides/sms/migrate.md. Use an existing authenticated Bird MCP or CLI connection. If neither is available, follow https://bird.com/docs/ai/set-up-your-agent.md. Discover the actual operations; do not invent commands or ask me to paste credentials into chat.
3. Prepare the code changes, sender/destination requirements, consent migration, webhook verification and rollout/rollback plan. Preserve the scope of each customer's preferences, including requests outside SMS replies. Separate API batches from audience broadcasts and preserve any behavior that has no direct endpoint equivalent.
4. Show me the exact affected resources, destinations, test volume and known costs before an action that sends messages, spends money, registers or changes a sender, or moves production traffic. Require explicit human authorization for each paid submission or production change. Name one-off 10DLC registration and resubmission fees before requesting approval. An existing explicit approval for that exact action is sufficient; broad migration approval is not. Simulated SMS destinations are billable and still require authorization.
5. If I am keeping Twilio numbers, prepare the human support port request and obtain authorization to send it. Read bird support-tickets create --help, then use the available CLI or MCP support operation with the reviewed number list and requirements. Return the ticket ID and follow the reply; support arranges the port on its own schedule, separately from the code cutover.
6. Run local and intercepted tests first. When authorized, perform the agreed bounded integration tests, inspect accepted and final outcomes separately, and report failures or uncertainty. Do not claim a delivery receipt proves reading or that request idempotency guarantees exactly-once delivery.
7. Keep production cutover and retiring the old provider as explicit steps in the approved rollout. Finish with the diff, evidence, unresolved requirements and the next action.