ci: simplify release body and doc

Author: piotr-roslaniec

.github/workflows/release.yml

@@ -43,6 +43,4 @@ jobs:
         with:
           tag_name: ${{ github.ref_name }}
           name: Release ${{ github.ref_name }}
-          body: |
-            Automated release for ${{ github.ref_name }}.
-            See CHANGELOG.md for details.
+          body: Release ${{ github.ref_name }}. See CHANGELOG.md for details.

RELEASE.md

@@ -16,4 +16,4 @@ Process for publishing tagged Go module releases for this fork of `keep-common`.
 ## Tagging & Publishing
 1) Tag: `git tag -a vX.Y.Z -m "Release vX.Y.Z"` (or `vX.Y.Z-tlabs.N` for fork-specific releases).
 2) Push tag: `git push origin vX.Y.Z[-tlabs.N]`.
-3) CI: pushing a `v*` tag triggers the release workflow to regenerate code, run vet/tests, and publish a GitHub release. The release body can be edited afterward to include the changelog excerpt and upstream baseline notes if needed.
+3) CI: pushing a `v*` tag triggers the release workflow to regenerate code, run vet/tests, and publish a GitHub release with a placeholder body referencing `CHANGELOG.md`. Edit the GitHub release afterward to paste the changelog excerpt and upstream baseline notes.