docs(readme): restore version badge for Copilot SDK; ci: add skip-release support and README link injection [skip release]

- add static v0.9.1 badge to Copilot SDK Star Features heading

- inject plugin README link before each embedded v*.md in release body

- skip release workflow when commit message contains [skip release]

.github/workflows/release.yml

@@ -57,6 +57,8 @@ permissions:
 jobs:
   check-changes:
     runs-on: ubuntu-latest
+    # Skip release if commit message contains [skip release]
+    if: ${{ !contains(github.event.head_commit.message, '[skip release]') }}
     env:
       LANG: en_US.UTF-8
       LC_ALL: en_US.UTF-8
@@ -370,6 +372,11 @@ jobs:
               while IFS= read -r file; do
                 [ -z "$file" ] && continue
                 if [ -f "$file" ]; then
+                  # Inject plugin README link before each release note file content
+                  plugin_dir=$(dirname "$file")
+                  readme_url="https://github.com/Fu-Jie/openwebui-extensions/blob/main/${plugin_dir}/README.md"
+                  echo "> 📖 [Plugin README](${readme_url})" >> release_notes.md
+                  echo "" >> release_notes.md
                   cat "$file" >> release_notes.md
                   echo "" >> release_notes.md
                 fi