Name the package each controller-repository image compiles, and say a renamed file under both names (hq ADR 0267, issue 363)

Every merge to the controller's repository rebuilt the route proxy and the
build seat's holder, because their builds read that repository whole. Named,
the build seat hands each only its program's build source and the planner
moves each only when that changes. A rename was said under its new name
alone, so a file moved out of a build source changed nothing the planner
could see.

modules/route-proxy/Dockerfile

@@ -5,7 +5,10 @@ ARG GO_BASE=golang:1.25
 # **The proxy source is not vendored here.** The canonical proxy — the contract written as something
 # that runs — lives in the mesh-controller repository at examples/route-proxy (novox/hq 08-connectivity
 # §3). This module ships the *packaging*, not a second copy of the contract, so the build context is
-# the mesh-controller repository root, and this Dockerfile compiles ./examples/route-proxy from it.
+# the mesh-controller repository, and this Dockerfile compiles ./examples/route-proxy from it. The build seat
+# hands it only that program's build source — its import closure, go.mod, go.sum and the vendored packages
+# it uses (novox/hq ADR 0267, the artifact's `compiles`) — so a merge elsewhere in that repository does not
+# move this image, and a COPY of anything outside it fails by name.
 #
 #   docker build -f mesh-catalog/modules/route-proxy/Dockerfile \
 #                -t mesh-route-proxy:development  <path-to>/mesh-controller