Buffer aliasing (local buffer assignment) not supported

Declaring a buffer block, for example a RWStructuredBuffer with an assignment, ignores the right hand side. Making the following code compile without errors or warnings.
The assignment should clearly validate the assigned type and also copy over any applicable layout specifications, such as `binding` and `set`.

```hlsl
static const float TestValue = 1;

void main()
{
RWStructuredBuffer values = TestValue;
values[0] = 0;
}
```

Start by reproducing the HLSL example with glslang and trace how buffer declarations and local assignments are handled. The work is done when the assigned type is validated and applicable layout specifications such as binding and set are copied without errors or warnings.

Written by the indexing model from the issue text.