Qubit number validation in Squin

[weinbe58]

Part of integration with hardware needs to be able to determine the number of qubits (given arguments). IMO we have two options:

1. Error if we cannot statically infer the number of qubits at compile time
2. Run a dummy interpreter that keeps track of the total number of qubits used during execution.

[weinbe58]

We're going to stick with 1.