docs: note how the module resolves and verify it in release-check

Assisted-by: GLM 5.3 Flash

README.md

@@ -40,6 +40,11 @@ go get sourcedock.dev/petrbalvin/interpres/v2
 
 Requires Go 1.27.1 or newer. The module imports only the standard library.
 
+The module is public and resolves through proxy.golang.org and sum.golang.org
+like any other; no GOPROXY or GOPRIVATE setup is needed to fetch it. A machine
+that sets `GOPRIVATE=sourcedock.dev` fetches directly from the forge instead,
+which skips the proxy and the checksum database.
+
 ## Quick start
 
 ```sh

justfile

@@ -134,6 +134,8 @@ release-check version:
     print qq{branch, tree, sync and changelog verified; running the gates\n};
     system(qw{just gates}) == 0 or die qq{release-check: the gates failed\n};
     print qq{release-check: ready to release $version\n};
+    print qq{after tagging, verify the /v2 module resolves through the proxy:\n};
+    print qq{  cd \$(mktemp -d) && go mod init t && GOPRIVATE= GOPROXY=https://proxy.golang.org go get sourcedock.dev/petrbalvin/interpres/v2\@$version\n};
 
 # Compares the toml-test counts the documentation names with the live suite run; not standard, it exists because a corpus change used to be corrected by hand.
 docs-drift: