Use chalice deploy to only update lambda

Is there a way to use `chalice deploy` to only update a lambda function?

Currently, I have an existing API Gateway that has several routes defined. Each of these routes point to a different lambda function. E.g.,:
```
APIGateway X
│
└───/endpoint1 --> Points to lambda1
│
└───/endpoint2--> Points to lambda2
....
│
└───/endpoint --> Points to lambda
```

The creation of resources (APIG and Lambdas) is handled via Terraform and the deployment of lambdas is being handled by a legacy CI system using `aws --profile lambda update-function-code --function-name --zip-file --publish` command. Not all of this lambdas live in the same repository and its not possible to house them together at this point. But I want to move away from this system and exploring the possibility of using chalice's deployment capabilities. The problem is I can't change the existing architecture since that's a huge lift.

So essentially I want to only update the lambda code using chalice and not touch any other resources. Is this possible to do? I went over https://github.com/aws/chalice/issues/604 but didn't find a viable solution.

Start by reviewing issue #604 and the deployment behavior described in this issue, then inspect how Chalice handles existing API Gateway and Lambda resources. Determine whether deployment can update only Lambda code while leaving Terraform-managed resources untouched; done means a clear supported approach or a documented limitation.

Written by the indexing model from the issue text.