Create flipper-server-client package

Summary:
FlipperServerClient is a useful abstraction for any JS-based client of headless Flipper. No need to bundle it with flipper-frontend-core, as the rest is not useful for external clients.
Currently, I am planning to add it to jest-e2e to send commands to Flipper

Reviewed By: lblasa

Differential Revision: D40765668

fbshipit-source-id: af48710bb15444ac1ecd649fe9a2ab252f3088f3

desktop/flipper-server-client/src/index.tsx

@@ -0,0 +1,10 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+export * from './FlipperServerClient';