Here is a list of all documented files with brief descriptions:

[detail level 12345]

packs
rigProject
src
rig
pages.h	Page board helpers - make CPage entities and pan / zoom the board
AddSerializer.h	Templates that register one component codec on a document registry
ContractImport.h	Read a Contract document into the ECS and report what arrived
EntityIdRemap.h	Entity handles as document id strings, and reference fixup after a load
FaceInsets.h	Six face insets on a local AABB (same cuboid as rig.spatial.anchor)
ProjectJson.h	Ordered JSON read and write for Rig documents, plus the Contract version stamp
ProjectSerializer.h	Save and load the ECS as a Rig Contract document other hosts can read
Rigz.h	Open a .rig or .rigz package and resolve the asset paths inside it