[TRI-1169] Create a Vercel integration package

[ericallam]

Vercel have webhook events that we could be exposed through a @trigger.dev/vercel integration:

https://vercel.com/docs/observability/webhooks-overview/webhooks-api

They also have an API for registering webhooks that we can use:

https://vercel.com/docs/rest-api/endpoints#webhooks

Useful docs/code

• Development guide
• Create integration guide
• Other integration packages, especially ones with webhooks like GitHub, Typeform, and Linear.

Requirements

• Make sure that you have fully tested that each webhook works and comes through to your locally running dashboard
• Make sure you've implemented the best practice security in verifying the payloads. Vercel talk about this in their linked docs above.
• Make sure to add Vercel to the integrationCatalog.

_{From SyncLinear.com | TRI-1169}

[Chigala]

@ericallam I'll love to work on this. Pls assign this to me.

[Tushar98644]

@matt-aitken I would love to take up the issue if no one is working on it

[hmacr]

@ericallam Do we want to support just the webhooks in this integration?

Vercel does not have an official SDK that provides its API functions.
SDK - Vercel Client / Available Functions

If we plan to provide their API functions as tasks (say create_env_var, edit_env_var, etc.), we'll have to write our own wrapper using native fetch. Do we want to support Vercel tasks as part of this integration?
API Reference

[hmacr]

@ericallam Apologies for the reminder.
I'm about to start on the Webhooks part and would like your view on the above query.

[ericallam]

Yea I think let's try and support the webhooks and any other that might be useful, but don't have to be an exhaustive support from the beginning 👍