Added README files in v2 proto directories. (#812)

Signed-off-by: Cody Littley <cody@eigenlabs.org>

api/proto/README.md

@@ -0,0 +1,44 @@
+# A note about experimental/WIP APIs
+
+There are a number of APIs that are currently under active development. These APIs can be fully ignored.
+All such APIs will have comments in the form
+
+```
+/////////////////////////////////////////////////////////////////////////////////////
+// Experimental: the following definitions are experimental and subject to change. //
+/////////////////////////////////////////////////////////////////////////////////////
+```
+
+The majority of the WIP APIs are for a project we are calling internally `EigenDA v2 Architecture`.
+More on that below.
+
+## Q: Which APIs are currently experimental?
+
+The following APIs are currently experimental:
+- `disperser/v2/*`
+- `lightnode/*`
+- `node/v2/*`
+- `relay/*`
+
+## Q: are APIs not marked with "Experimental" stable?
+
+Yes. We are commited to maintaining backwards compatibility for all APIs that are not marked as experimental,
+and any breaking changes will be made only after a long deprecation period and active communication with
+all stakeholders. Furthermore, breaking API changes are expected to be rare.
+
+## Q: Should I use experimental APIs?
+
+No. No experimental APIs are currently deployed to any public environments. In general, assume
+that experimental APIs are not functional absent messaging from the EigenDA team declaring otherwise.
+
+## Q: Are experimental APIs stable?
+
+No, although they will become more and more stable as they reach maturity.
+
+## Q: What is "v2"?
+
+The EigenDA v2 Architecture is a fundamental redesign of the protocol. The v2 Architecture improves robustness,
+efficiency, and paves the way for upcoming features such as permissionless disperser instances
+and data availability sampling.
+
+We intend on publishing a more detailed roadmap and design overview in the near future, stay tuned!