fix: reading version bump from changelog

Author: cs-raj

.github/workflows/check-version-bump.yml

@@ -67,10 +67,16 @@ jobs:
           }
 
           head_version=$(extract_version < "$VERSION_FILE")
-          CHANGELOG_HEAD=$(sed -nE 's/^## v?([^[:space:]]+).*/\1/p' "$CHANGELOG_FILE" | head -1)
+          # Changelog uses "## Date" sections with versions on "#### vX.Y.Z" lines; support that and legacy "## vX.Y.Z".
+          CHANGELOG_HEAD=$(
+            sed -nE 's/^####[[:space:]]+v?([0-9]+\.[0-9]+\.[0-9]+).*/\1/p' "$CHANGELOG_FILE" | head -1
+          )
+          if [ -z "$CHANGELOG_HEAD" ]; then
+            CHANGELOG_HEAD=$(sed -nE 's/^##[[:space:]]+v?([0-9]+\.[0-9]+\.[0-9]+).*/\1/p' "$CHANGELOG_FILE" | head -1)
+          fi
 
-          [ -n "$CHANGELOG_HEAD" ] || { echo "::error::Could not find a top changelog heading like '## vX.Y.Z' in $CHANGELOG_FILE."; exit 1; }
-          [ "$CHANGELOG_HEAD" = "$head_version" ] || { echo "::error::$CHANGELOG_FILE top version ($CHANGELOG_HEAD) does not match project version ($head_version)."; exit 1; }
+          [ -n "$CHANGELOG_HEAD" ] || { echo "::error::Could not find a version in $CHANGELOG_FILE (expected '#### vX.Y.Z' under a date section or legacy '## vX.Y.Z')."; exit 1; }
+          [ "$CHANGELOG_HEAD" = "$head_version" ] || { echo "::error::$CHANGELOG_FILE top release version ($CHANGELOG_HEAD) does not match project version ($head_version)."; exit 1; }
 
           base_version=$(git show "$BASE_SHA:$VERSION_FILE" | extract_version)
           latest_tag=$(git tag --list 'v*' --sort=-version:refname | sed -n '1p')