Update README about new step-summary and revised thread comments

[shenxianpeng]

We need to update README.md

1. Add optional input about the new feature "step-summary" (maybe need to add a screenshot)
2. Update existing screenshots about thread comments (e.g 1045e02)

[shenxianpeng]

It might be better to update the introduction in README and action.yml to include step-summary and add a screenshot of step-summary to the README.
It is not necessary to create a tag immediately for release, just merge to the main branch if the new changes look good.

These places, for example, better be updated

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.

Lint C/C++ code with clang-format and clang-tidy then post annotations and comments with faulty results.

[2bndy5]

I added a link to the github docs (in #152) alluding to the misconception about "step summary" vs "job summary". Maybe the new screenshot could also have a caption that would help clear any remaining confusion.

[shenxianpeng]

Yes, see it, the link to the job summary is helpful. A screenshot could let the user know what it looks like in a real project and may want to use it. Reopen to track the rest updated.