Fix missing images on English pages

Hugo only auto-shares page-bundle resources across translations when
each language has its own content directory; with filename-based
translation (index.fr.md / index.en.md in the same folder) a resource
with no language code is assigned to the default language only. Add
.en.-suffixed copies of every image referenced from English pages and
point the English markdown at them.

content/documentation/VXLAN/beginners/vxlan-for-beginners.en.md

@@ -55,7 +55,7 @@ The goal of **VXLAN** is to **extend layer 2** across a layer 3 (IP) network. Th
 
 > **In plain terms:** Ethernet frames (layer 2) are encapsulated inside a UDP packet (layer 4), which is itself carried over IP (layer 3).  
 
-![OSI Layers](media_layers.fr.png#center)
+![OSI Layers](media_layers.en.png#center)
 
 > [!NOTE]**The "hardware" layers**  
 >
@@ -87,7 +87,7 @@ The train runs on rails (the **IP network**, layer 3). The rail tracks are alrea
 - **Isolation and segmentation:** Just as several trains can run on the same railway line, it's possible to operate different VXLAN tunnels (each with its own VNI) over the same IP infrastructure.  
 - **Elasticity and reliability:** By relying on layer 3, VXLAN benefits from all the optimizations of IP routing (route recalculation, fault tolerance, etc.).  
 
-![Container transport](transports.fr.png#center)
+![Container transport](transports.en.png#center)
 
 ## Real-world use cases 🏭