Support pre-built layer archives in the start-api command

### Describe your idea/feature/enhancement

Stack: Python, APIGateway, Lambda
When we use `sam local start-api --use-container`, we usually use it to make sure the dependencies get built on the right platform. But if we use `--use-container`, changes to the code are no longer picked up automatically, making the start-api feature less useful as we have to kill the local server and restart to refresh the changes.

### Proposal

Add a switch to all local invocations including start-api to package the container with a layer folder or archive. This way, we can build the layer with the platform specific stuff once and point all local invokes to pick the layer from that folder or archive