docs: note PR URL search in changelog

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

Author: grimmerk

CHANGELOG.md

@@ -4,7 +4,7 @@
 
 - Fix: menubar Keyboard Shortcuts submenu now reflects custom shortcuts
 - Fix: GitHub release notes now aggregate all unreleased changelog entries
-- Feat: PR link badge in session list items (clickable, opens browser)
+- Feat: PR link badge in session list items (clickable, opens browser, searchable by URL)
 - Feat: purple dot on projects currently open in VS Code/Cursor
 - Pin axios to 1.14.0 (avoid compromised 1.14.1)