docs: partial response and pipeline diagrams

pipeline/README.md

@@ -46,6 +46,10 @@ Wikipedia says
 
 > In software engineering, a pipeline consists of a chain of processing elements (processes, threads, coroutines, functions, etc.), arranged so that the output of each element is the input of the next; the name is by analogy to a physical pipeline.
 
+Flowchart
+
+![Pipeline flowchart](./etc/pipeline-flowchart.png)
+
 ## Programmatic Example of Pipeline Pattern in Java
 
 Let's create a string processing pipeline example. The stages of our pipeline are called `Handler`s.