Add architecture graph in readme

README.md

-# the-software-graph
+# Software Graph
+
+[TOC]
+ 
+## Architecture
+
+```mermaid
+%%{ init : { "flowchart" : { "curve" : "stepAfter" }}}%%
+
+flowchart BT;
+subgraph Containers
+    B(Backend FastAPI<br>:8000)
+    F([Frontend Svelte<br>:5173])
+    R[(Redis Cache<br>:6379)]
+    N[(Neo4j Graph Database<br>:7474<br>:7687)]
+end
+B---F
+B---R
+B---N
+subgraph Volumes
+    VB[Volume Backend Code]
+    VF[Volume Frontend Code]
+    VN[Volume Neo4j data]
+end
+VB---B
+VF---F
+VN---N
+
+
+```
+
 
 ## En cas d'erreur
 `neo4j | Folder /data is not accessible for user: 7474 or group 7474 or groups 7474, this is commonly a file permissions issue on the mounted folder.`
 
 Solution:
 
-`sudo chmod -R 777 neo4j/data`
\ No newline at end of file
+`sudo chmod -R 777 neo4j/data`