Add doc for /setup-github command to install workflows (#78)

Add doc for /setup-github command to install workflows

Author: JeromeJu

workflows/gemini-cli/README.md

@@ -36,7 +36,9 @@ In this guide you will learn how to use the general Gemini CLI workflow via GitH
 
 For detailed setup instructions, including prerequisites and authentication, please refer to the main [Getting Started](../../README.md#getting-started) and [Configuration](../../README.md#configuration) documentation.
 
-To use this workflow, copy the `gemini-cli.yml` file into your repository's `.github/workflows` directory:
+To use this workflow, you can utilize either of the following steps:
+1. Run the `/setup-github` command from Gemini-CLI to set up workflows for your repository.
+1. Copy the `gemini-cli.yml` file into your repository's `.github/workflows` directory:
 
 ```bash
 mkdir -p .github/workflows

workflows/issue-triage/README.md

@@ -49,7 +49,9 @@ The two workflows work together to ensure that all new and existing issues are t
 
 For detailed setup instructions, including prerequisites and authentication, please refer to the main [Getting Started](../../README.md#getting-started) and [Configuration](../../README.md#configuration) documentation.
 
-To implement this issue triage system, copy the workflow files into your repository's `.github/workflows` directory:
+To implement this issue triage system, you can use either of the following steps:
+- Run the `/setup-github` command from Gemini-CLI to set up workflows for your repository.
+- Copy the workflow files into your repository's `.github/workflows` directory:
 
 ```bash
 mkdir -p .github/workflows

workflows/pr-review/README.md

@@ -47,7 +47,9 @@ The PR Review workflow uses Google's Gemini AI to provide comprehensive code rev
 
 For detailed setup instructions, including prerequisites and authentication, please refer to the main [Getting Started](../../README.md#getting-started) and [Configuration](../../README.md#configuration) documentation.
 
-To use this workflow, copy the `gemini-pr-review.yml` file into your repository's `.github/workflows` directory:
+To use this workflow, you can use either of the following steps:
+1. Run the `/setup-github` command from Gemini-CLI to set up workflows for your repository.
+1. Copy the `gemini-pr-review.yml` file into your repository's `.github/workflows` directory:
 
 ```bash
 mkdir -p .github/workflows