docs: update CHANGELOG.md for 0.4.8 (#74)

Co-authored-by: jorben <2806170+jorben@users.noreply.github.com>

Author: jorben

CHANGELOG.md

@@ -4,6 +4,11 @@ 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).
 
+## [0.4.8] - 2026-05-13
+### :sparkles: New Features
+- [`53e1d43`](https://github.com/MarkPDFdown/markpdfdown-desktop/commit/53e1d4398b0d38d2d0985aa9cbf898c25dfc6aa9) - **provider**: ✨ Add ZenMux promo banner *(PR [#73](https://github.com/MarkPDFdown/markpdfdown-desktop/pull/73) by [@jorben](https://github.com/jorben))*
+
+
 ## [0.4.7] - 2026-05-08
 ### :bug: Bug Fixes
 - [`b4752fd`](https://github.com/MarkPDFdown/markpdfdown-desktop/commit/b4752fd3f7fb64308d7fb36613b68ce7c5cac3d4) - **cloud**: 🐛 optimize context and debounce SSE refresh *(PR [#70](https://github.com/MarkPDFdown/markpdfdown-desktop/pull/70) by [@jorben](https://github.com/jorben))*
@@ -195,3 +200,4 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 [0.4.5]: https://github.com/MarkPDFdown/markpdfdown-desktop/compare/0.4.3...0.4.5
 [0.4.6]: https://github.com/MarkPDFdown/markpdfdown-desktop/compare/0.4.5...0.4.6
 [0.4.7]: https://github.com/MarkPDFdown/markpdfdown-desktop/compare/0.4.6...0.4.7
+[0.4.8]: https://github.com/MarkPDFdown/markpdfdown-desktop/compare/0.4.7...0.4.8