fix: audit LOW fixes — rejection-path tests, wallpaper-fallback docs (v0.9.1)

- Test AccountsService-icon symlink rejection (users.rs)
- Tests for wallpaper symlink/extension/size rejection (config.rs)
- Fix stale 'bundled package wallpaper' fallback docs (README, example config) — bundled tier removed 2026-03-28, actual chain is two-tier

CHANGELOG.md

@@ -3,6 +3,16 @@
 All notable changes to this project will be documented in this file.
 Format based on [Keep a Changelog](https://keepachangelog.com/).
 
+## [0.9.1] - 2026-06-17
+
+### Fixed
+
+- Wallpaper fallback docs (README, example config) referenced a removed "bundled package wallpaper" tier; corrected to two-tier (config → moonarch default → CSS background)
+
+### Added
+
+- Tests for avatar/wallpaper rejection paths (AccountsService symlink, wallpaper symlink/extension/size)
+
 ## [0.9.0] - 2026-06-17
 
 ### Changed