(punition): No more working on backend until Maieul says so :(

src/tic-tac-toe/README.md

@@ -1,6 +1,18 @@
+# Directory layout
+```plaintext
+./src/tic-tac-toe
+├── entrypoint.sh
+├── package.json
+├── README.md
+├── src
+│   ├── app.ts      # The microservice app file, where the major part of the backend code lives.
+│   └── run.ts      # Equivalent of server.ts, it is the entrypoint for our service.
+├── tsconfig.json
+└── vite.config.js
+```
+
 # Anatomy of a microservice
 
 # Backend
 
-# Frontend
-
+# Frontend