Arguments that are "Dynamic Constant" treated as "Static" across callable boundaries

[swernli]

(Note this repro depends on the bug in #3282, so if that is fixed first then a different repro may be needed)

When RCA determines the runtime capabilities of a callable invocation it uses the callable's application generator set and checks the dynamism of each argument to know wich capabiltiies to aggregate. However, only arguments that are "Dynamic Variable" are checked, the rest are assumed to be "Static" arguments. Internally, we effectively have three categories of values: Static, Dynamic Constant, or Dynamic Variable. By effectively promoting Dynamic Constant values into Static values, we lose some information across function calls. Using a specific repro, we can see that Q# expressions that generates an error if used directly is accepted if it is instead put in a function:

import Std.Arrays.IsEmpty;
@EntryPoint(Base)
operation Main() : Unit {
    use qs = Qubit[2];
    while IsEmpty(qs) {}
    LoopOnArray(qs);
}

function LoopOnArray(arr : Qubit[]) : Unit {
    while IsEmpty(arr) {}
}

Commenting out the explicit while in the body of Main will avoid errors and successfully generate QIR (as explained in #3282, the capabilities error is incorrect). This shows that code in a callable is treated different than code across callables, which can cause problems if things like classical loops are supposed to be emitted based on Dynamic Constant values.

[swernli]

Since #3286 has a fix that invalidates the repro, here is a new one relative to those changes:

struct Val {
    x : Int,
}

@EntryPoint(Base)
operation Main() : Unit {
    use qs = Qubit[1];
    let x = Length(qs);
    // new Val { x = x};
    MakeVal(x);
}

function MakeVal(x : Int) : Val {
    new Val { x = x}
}

This code works during QIR generation, but fails if the line that matches the function body is uncommented with an error about dynamic struct constructor expressions. This shows the same issue: properties of dynamism are lost across callable boundaries.