[compiler] flatten module exports to allow job diagnostics

[stuartc]

All jobs are written with the assumption the functions will be injected at some point.
Jobs essentially have a const { a, b,c } = require(<adaptor>); prepended to them, it's technically a little different but the effect is the same.

In order for the typescript compiler to provide diagnostics (and without changing how Jobs are written) we should 'flatten' the export members of our dts files.

The compiler will then see export declare function foo().. as declare function foo()....