Define formal processes for determining maturity and featured status of projects

So far the maturity of projects and their featured status has been a "finger in the air estimate", which is flaky, unfair, and impossible to automate.

We need a formal process to assess the maturity and featured status of all projects, including
- [ ] Clients
- [ ] Servers
- [ ] Bots
- [ ] Bridges
- [ ] SDKs

keywords: policy

The issue proposes a policy for assessing maturity and featured status across clients, servers, bots, bridges, and SDKs, but names no files, tests, or process details. Start by reading the existing project listings and any current criteria for featured status; done means a formal, consistently applicable assessment process is defined for all listed project types.

Written by the indexing model from the issue text.