Updates to the extensibility overview page (#34792)

* Moved images to their own folder, and added backgrounds
Added links to related docs

* Update image paths in YARP extensibility doc (#34796)

* Update image paths in YARP extensibility doc

* xref over relative file links

* xref over relative file links

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Co-authored-by: Sam Spencer <[email protected]>
Co-authored-by: Rick Anderson <[email protected]>

Author: 3 people

aspnetcore/fundamentals/servers/yarp/extensibility.md

@@ -21,17 +21,25 @@ There are 2 main styles of extensibility for YARP, depending on the routing beha
 
 YARP uses the concept of [Routes](xref:fundamentals/servers/yarp/config-files#routes), [Clusters](xref:fundamentals/servers/yarp/config-files#clusters) and Destinations. These can be supplied through [configuration files](xref:fundamentals/servers/yarp/config-files) or [directly through code](xref:fundamentals/servers/yarp/config-providers). Based on the routing rules, YARP picks a cluster and enumerates the possible destinations. It then uses the middleware pipeline to select the destination based on destination health, session affinity, load balancing etc.
 
-![Middleware pipeline diagram](https://github.com/user-attachments/assets/ff17a04f-0c3c-46c7-8ec2-a1ed3dbc948c)
+![Middleware pipeline diagram](~/fundamentals/servers/yarp/media/yarp-pipeline.png)
 
-Most of the pre-built pipeline modules can be customized through code. You can also change the pipeline definition to replace modules with your own implementation(s) or add additional modules as needed.
+Most of the pre-built pipeline can be customized through code:
 
-For more information see [Middleware](xref:fundamentals/servers/yarp/middleware).
+- [Configuration Providers](xref:fundamentals/servers/yarp/config-providers)
+- [Destination Enumeration](xref:fundamentals/servers/yarp/destination-resolvers)
+- [Session Affinity](xref:fundamentals/servers/yarp/session-affinity)
+- [Load Balancing](xref:fundamentals/servers/yarp/load-balancing)
+- [Health Checks](xref:fundamentals/servers/yarp/dests-health-checks)
+- [Request Transforms](xref:fundamentals/servers/yarp/transform-extensibility)
+- [HttpClient configuration](./http-client-config.md#code-configuration)
+
+You can also change the pipeline definition to replace modules with your own implementation(s) or add additional modules as needed. For more information see [Middleware](xref:fundamentals/servers/yarp/middleware).
 
 ## Http Forwarder
 
 If the YARP pipeline is too rigid for your needs, or the scale of routing rules and destinations is not suitable for loading into memory, then you can implement your own routing logic and use the HTTP Forwarder to direct requests to your chosen destination. The HttpForwarder component takes the HTTP context and forwards the request to the supplied destination.
 
-![HTTP forwarder diagram](https://github.com/user-attachments/assets/1a060a7e-fa43-49a4-bfad-f95d7d35be63)
+![HTTP forwarder diagram](~/fundamentals/servers/yarp/media/yarp-forwarder.png)
 
 The transform component can still be used with the forwarder is needed.