add step-summary screenshot and update introduction #151 (#153)

* add step-summary screenshot and update introduction #151

* Update action.yml

Co-authored-by: Brendan <2bndy5@gmail.com>

* Update README.md

Co-authored-by: Brendan <2bndy5@gmail.com>

---------

Co-authored-by: Brendan <2bndy5@gmail.com>

Author: 2 people

README.md

@@ -8,7 +8,7 @@
 [![MkDocs Deploy](https://github.com/cpp-linter/cpp-linter-action/actions/workflows/mkdocs-deploy.yml/badge.svg)](https://github.com/cpp-linter/cpp-linter-action/actions/workflows/mkdocs-deploy.yml)
 ![GitHub](https://img.shields.io/github/license/cpp-linter/cpp-linter-action?label=license&logo=github)
 
-A Github Action for linting C/C++ code integrating clang-tidy and clang-format to collect feedback provided in the form of thread comments and/or annotations.
+A Github Action for linting C/C++ code integrating clang-tidy and clang-format to collect feedback provided in the form of annotations, thread comments, and step summary.
 
 ## What's New
 
@@ -171,6 +171,10 @@ This action creates 1 output variable named `checks-failed`. Even if the linting
 
 ![sample comment](https://raw.githubusercontent.com/cpp-linter/cpp-linter-action/main/docs/images/comment.png)
 
+### Step Summary
+
+![step summary](https://raw.githubusercontent.com/cpp-linter/cpp-linter-action/main/docs/images/step-summary.png)
+
 <!--footer-start-->
 
 ## Add C/C++ Linter Action badge in README

action.yml

@@ -1,5 +1,5 @@
 name: C/C++ Linter
-description: Lint C/C++ code with clang-format and clang-tidy then post annotations and comments with faulty results.
+description: Lint C/C++ code with clang-format and clang-tidy then post annotations, comments, and step summary with results.
 author: shenxianpeng
 branding:
   icon: "check-circle"