Seperate the FIELD MAPPING and RULE BUILDER screens

There are some functions that only Mappers should see, and some functions that Developers should see.

One idea is to just commit to building two seperate screens so that we can purpose build a screen dedicated for FIELD MAPPERS to do the mapping without worrying about hiding or disabling features that a Developer should do.

Likewise when a Developer is reviewing and implementing the Mappings as RULES - they probably have a different set of Fields and Function that would make that task easier.

This has aspects of Functionality, Design, and probably a big Technical Impact - so more work required to figure out the pros / cons to splitting this.