Restyle category tree to idiomatic Bootstrap list-group pattern (v0.1.8)

Switch from custom link classes to Bootstrap's native list-group-item-action
pattern. Replace bold primary-colored active background with subtle tertiary
background, left accent border, and semibold text.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -2,6 +2,13 @@
 
 All notable changes to this project will be documented in this file.
 
+## [0.1.8] - 2026-03-29
+
+### Changed
+
+- **Category tree restyled** (`category-tree.html.twig`, `category-tree-node.html.twig`): Switched from custom link classes to Bootstrap's native `list-group-item list-group-item-action` pattern with nested collapse divs for a more idiomatic Bootstrap look
+- **Subtler active state** (`wc-bootstrap.css`): Replaced bold primary-colored background with light background (`var(--bs-tertiary-bg)`), left accent border (`3px solid var(--bs-primary)`), and semibold text for a less prominent highlight
+
 ## [0.1.7] - 2026-03-29
 
 ### Added