Add charter (values, membership, governance, evolution)

README.md

@@ -64,6 +64,8 @@ Privacy is a core value. The current backend (Ollama Cloud) is a policy-based pr
 
 The Inference Cooperative is fiscally sponsored by [Metagov](https://metagov.org). Members govern the project through [Loomio](https://www.loomio.com) and the Open Collective.
 
+See the [Charter](charter.md) for the cooperative's values, membership terms, and governance structure.
+
 ---
 
 *This documentation lives in a public git repository. Contributions welcome.*