name no consumer of this node

A source that documents itself through a specific downstream node depends on
that node to be understood, and that node already depends on this one for
frames. The README pointed at one by name and the CI workflow still carried a
comment about the dataflow that wired it, which no longer exists.

The output is documented by its type instead: wire `image` into anything that
takes std/media/v1/Image. PREVIEW covers seeing the frames without naming
anyone. Generic words like "a viewer" or "a consumer" stay, since they describe
a role rather than a repository.

README.md

@@ -48,8 +48,9 @@ A window opens showing the frames as they are published. Press `q` to stop. That
 enough to check a camera, an encoding or a flip without wiring a second node — which is
 why there is one dataflow here rather than one per consumer.
 
-For a real pipeline, wire `image` into a viewer such as `dora-image-view` from your own
-dataflow.
+For a real pipeline, wire `image` into any node that takes `std/media/v1/Image`, from
+your own dataflow. This repository names no consumer: it is a source, and depending on
+something downstream of it only to demonstrate it would be a cycle.
 
 ## Output