Align release preparation and tooling with the current Go version

docs/release.md

@@ -9,6 +9,25 @@ for CI to finish or succeed.
 Required tools are Git, Go with race-detector support, POSIX shell, and Python
 3. Publication requires push access to origin. Work from the repository root.
 
+Use the latest Go toolchain available in the development environment for
+release preparation and validation. Make that installation the active `go`
+command, then advance PromptKit's Go requirement before committing the
+candidate:
+
+```sh
+export GOTOOLCHAIN=local
+go version
+release_go_version=$(go env GOVERSION)
+go get "go@${release_go_version#go}"
+```
+
+Include the module change in the candidate commit. Describe a raised minimum
+Go requirement in the release note and select the release version under the
+[compatibility policy](policy/release.md#versioning-and-compatibility).
+Keep this toolchain active through validation and publication. Toolchain
+selection and the module update are preparation, not mutations of an already
+validated candidate.
+
 Select an unused version and create `docs/releases/<version>.md` using the
 [required structure](policy/release.md#release-documentation). Describe
 compatibility impact and consumer actions and update affected canonical docs.