[meta] add auto-changelog

.npmrc

@@ -1 +1,3 @@
 package-lock=false
+allow-same-version=true
+message=v%s

CHANGELOG.md

@@ -0,0 +1,6 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

package.json

@@ -46,7 +46,9 @@
 		"tests-only": "tape 'test/**/*.js'",
 		"tests-esm": "node test/index.mjs",
 		"test": "npm run tests-only && npm run tests-esm",
-		"posttest": "aud --production"
+		"posttest": "aud --production",
+		"version": "auto-changelog && git add CHANGELOG.md",
+		"postversion": "auto-changelog && git add CHANGELOG.md && git commit --no-edit --amend && git tag -f \"v$(node -e \"console.log(require('./package.json').version)\")\""
 	},
 	"repository": {
 		"type": "git",
@@ -74,6 +76,7 @@
 	"devDependencies": {
 		"@ljharb/eslint-config": "^17.1.0",
 		"aud": "^1.1.2",
+		"auto-changelog": "^2.2.0",
 		"eslint": "^7.7.0",
 		"functions-have-names": "^1.2.1",
 		"has-strict-mode": "^1.0.0",
@@ -83,5 +86,13 @@
 	"dependencies": {
 		"define-properties": "^1.1.3",
 		"es-abstract": "^1.18.0-next.0"
+	},
+	"auto-changelog": {
+		"output": "CHANGELOG.md",
+		"template": "keepachangelog",
+		"unreleased": false,
+		"commitLimit": false,
+		"backfillLimit": false,
+		"hideCredit": true
 	}
 }