Shard ID validation in Sandbox for deployments

[knazarov]

You can choose any shard number right now if you deploy the contract. If you try to press "deploy", you'd see the following in the log:

Deployment failed
Error: failed to estimate call fee: failed to call method Call on shard 1: failed to call method Call on shard 18: shard API not found

This is confusing on many levels. Just try to do that yourself and you'll see why. It even doesn't show the error in the same window you're in. So if you're on mobile device where the log window is obscured - you'd not be able to understand why the "deploy" button does nothing.