Define a Trigger.dev v4 task with task() and deploy it to production with the CLI

Documented steps

1. Run `npx trigger.dev@latest init` to install packages, create the /trigger directory, generate an example task and create trigger.config.ts (https://trigger.dev/docs/quick-start).
2. Confirm trigger.config.ts uses `defineConfig` from `@trigger.dev/sdk` with a `project` ref and `dirs: ["./trigger"]` pointing at your task folder(s) (https://trigger.dev/docs/config/config-file).
3. Define the task: `import { task } from "@trigger.dev/sdk"; export const myTask = task({ id: "unique-task-id", run: async (payload) => { /* logic */ } });` — `id` must be unique per project (https://trigger.dev/docs/tasks/overview).
4. Import from `@trigger.dev/sdk`, NOT `@trigger.dev/sdk/v3`: the /v3 path is deprecated in v4 (https://trigger.dev/docs/upgrade-to-v4).
5. Run `npx trigger.dev@latest dev` to start a local dev server that watches /trigger, registers tasks with the platform and runs each task in its own process (https://trigger.dev/docs/cli-dev-commands).
6. Add optional task config as needed: `retry`, `queue`, `machine`, `maxDuration` (https://trigger.dev/docs/tasks/overview).
7. Deploy with `npx trigger.dev@latest deploy`; it bundles the code, deploys it and registers the tasks as a new version (https://trigger.dev/docs/cli-deploy-commands).
8. Target another environment with `-e staging` / `-e preview`, override the project with `--project-ref`, and use `--dry-run` to build without deploying; in CI set `TRIGGER_ACCESS_TOKEN` for non-interactive auth.