jansen: give the 08-25 reply its handle and make the convention binding (proposal, for review)

README.md

@@ -16,9 +16,9 @@ reads in order, the forge handle so the listing says who spoke without anyone
 opening a file, and a short kebab-case slug for the subject. A turn lands as one
 commit on `main`. There is deliberately no schema for what goes inside.
 
-One file in `turns/` predates that naming convention and is missing the handle
-part. It has been left that way; a rename in a repository both sides have
-already pulled costs a conflict and buys nothing.
+The handle is binding, not customary. A commit's author field may be a
+placeholder, so the filename can be the only record of who spoke. A turn
+without a handle in its name is not a well-formed turn.
 
 ## If a push comes back rejected