Update P2P-reading-in-weed-mount.md

P2P-reading-in-weed-mount.md

@@ -9,17 +9,17 @@ The design is documented in [design-weed-mount-peer-chunk-sharing.md](https://gi
 ## How it works at a glance
 
 ```mermaid
-flowchart LR
+flowchart TB
     Filer["Filer<br/>mount registry"]
+    Volumes["Volume servers"]
     MountA["weed mount"]
     MountB["weed mount"]
-    Volumes["Volume servers"]
 
     MountA --- Filer
     MountB --- Filer
-    MountA <-- "peer fetch" --> MountB
     MountA -. "fallback" .-> Volumes
     MountB -. "fallback" .-> Volumes
+    MountA <-- "peer fetch" --> MountB
 ```
 
 ### Chunk read sequence