docs: install jscpd and update docs

.jscpd.json

@@ -0,0 +1,3 @@
+{
+  "reporters": ["consoleFull", "markdown", "badge"]
+}

.markdownlintignore

@@ -1,4 +1,5 @@
 node_modules/
 /.github/vale_styles/
+/report/
 /docs/CHANGELOG.md
 /docs/CODE_OF_CONDUCT.md

.releaserc.yml

@@ -28,6 +28,7 @@ plugins:
         - package.json
         - package-lock.json
         - npm-shrinkwrap.json
+        - report
   -
     - "@semantic-release/exec"
     - publishCmd: "bin/build.sh && bin/publish.sh"

README.md

@@ -5,6 +5,7 @@
 [![Test](https://github.com/haru52/convertflac/actions/workflows/test.yml/badge.svg)](https://github.com/haru52/convertflac/actions/workflows/test.yml)
 [![Release](https://github.com/haru52/convertflac/actions/workflows/release.yml/badge.svg)](https://github.com/haru52/convertflac/actions/workflows/release.yml)
 [![CodeQL](https://github.com/haru52/convertflac/actions/workflows/github-code-scanning/codeql/badge.svg)](https://github.com/haru52/convertflac/actions/workflows/github-code-scanning/codeql)
+[![Copy/Paste](report/jscpd-badge.svg)](report/jscpd-report.md)
 [![Contributor Covenant](https://img.shields.io/badge/Contributor%20Covenant-2.1-4baaaa.svg)](https://haru52.github.io/convertflac/CODE_OF_CONDUCT.html)
 [![Commitizen friendly](https://img.shields.io/badge/commitizen-friendly-brightgreen.svg)](https://commitizen.github.io/cz-cli/)
 [![semantic-release: conventionalcommits](https://img.shields.io/badge/semantic--release-conventionalcommits-e10079?logo=semantic-release)](https://github.com/semantic-release/semantic-release)