fix: remove skills handling from version-bump and release workflows

Skills are not versioned in the registry. Their versioning happens in
the source repos. The version-bump workflow only handles modules, and
the release.yml skill-path detection was based on the old per-skill
directory format that no longer exists.

.github/workflows/release.yml

@@ -34,12 +34,7 @@ jobs:
           echo "module=$MODULE" >> $GITHUB_OUTPUT
           echo "version=$VERSION" >> $GITHUB_OUTPUT
 
-          # Determine whether this tag is for a module or a skill.
-          if [ -d "registry/$NAMESPACE/skills/$MODULE" ]; then
-            echo "module_path=registry/$NAMESPACE/skills/$MODULE" >> $GITHUB_OUTPUT
-          else
           echo "module_path=registry/$NAMESPACE/modules/$MODULE" >> $GITHUB_OUTPUT
-          fi
 
           RELEASE_TITLE="$NAMESPACE/$MODULE $VERSION"
           echo "release_title=$RELEASE_TITLE" >> $GITHUB_OUTPUT

.github/workflows/version-bump.yaml

@@ -5,7 +5,6 @@ on:
     types: [labeled]
     paths:
       - "registry/**/modules/**"
-      - "registry/**/skills/**"
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}