docs(dump): add changelog

src/CHANGELOG.md

@@ -0,0 +1,22 @@
+# Changelog
+
+All notable changes to AeonDumpManager will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+### Added
+
+- List, create, and delete SQL database dumps from a Settings admin page (nested under Settings, per
+  Shopware's [Add Menu Entry](https://developer.shopware.com/docs/v6.6/guides/plugins/plugins/administration/routing-navigation/add-menu-entry.html)
+  guide) and via `aeon:dump:list`/`aeon:dump:create`/`aeon:dump:remove` console commands.
+- Dumps are created with `mysqldump`/`mariadb-dump` (auto-detected, with an optional `dumpBinaryName`
+  override), gzip-compressed, and stored in the plugin's private Flysystem mount.
+- `maxDumps` auto-purges the oldest dump on creation; `retantionDays` purges dumps and stale job rows
+  on a recurring scheduled task.
+- Admin UI dump creation runs asynchronously via Symfony Messenger with a polling progress bar; console
+  creation runs synchronously.
+- ACL-gated (`aeon_dump_manager.viewer`/`.creator`/`.deleter`), enforced both client-side and
+  server-side.