Scope generated checks in a way that prevents them from being named

[the10thWiz]

I found out that you can scope items inside a constant's declaration block, which makes it impossible to refer to them outside of the block. I adjusted codegen to output checks like this:

const _: () = {
    /* checks */
};

Since it's impossible to refer to anything in the constant's declaration block, it cannot possibly conflict with anything the user wishes to declare. I also took a moment to change the module name to be easier to read.