Document role progression

[joewxboy]

How does a person go from a User to a Contributor to a Maintainer?

Roles are initially described in the wiki.

Some details may be alluded to or inferred in the Project's Technical Charter.

Also, in the LF Edge - Stage Three maturity, acceptance criteria, it lists specific files that should exist. The CONTRIBUTING.md file should be the canonical source of information about roles, progression, and how to contribute to the project. The wiki may expand on some of this, but it's important that the two locations (wiki and CONTRIBUTING) link to each other, and that all other locations (like documentation best practices repo wiki) also link to those two locations.

Separately, we should auto-generate (GHA) a central list of CONTRIBUTORS and MAINTAINERS, likely separated into "Active" and "Emeritus" sections depending on date of last contribution (one year? TSC should weigh in on this).