ESSL Shader generation COMPLETE and REDUCED options under/over expose uniforms

## Issue

The ESSL shader generator does not appear to work the same as the GLSL one when determining what uniforms to promote as "public" based on the "COMPLETE" and "REDUCED" interface options for generation.

The "REDUCED" options appears to remove all nodegraph inputs, and "COMPLETE" includes all nodegraph and interior node inputs.

Not sure why this differs but it makes it so that you get way to many or no inputs exposed for purposes such as UI display.

Start by comparing the ESSL and GLSL shader generators' handling of the COMPLETE and REDUCED interface options, then reproduce how nodegraph and interior-node inputs are exposed as public uniforms. Done means ESSL exposes the same intended uniform set as GLSL without exposing all inputs or removing them all.

Written by the indexing model from the issue text.