Update extension icon to new purple design (#362)

* Initial plan

* Update extension icon to new purple design

Co-authored-by: garrytrinder <11563347+garrytrinder@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: garrytrinder <11563347+garrytrinder@users.noreply.github.com>

Author: Copilot

CHANGELOG.md

@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed:
 
+- Icon: Updated extension icon to new purple design
 - Snippets: All snippets that reference schemas updated to use `v2.3.0` schema
 
 ## [1.14.0] - 2026-03-04