www/angie-module-cache-purge: Update 2.5.6 => 3.0.2

Changelog:
https://github.com/nginx-modules/ngx_cache_purge/releases/tag/3.0.0
https://github.com/nginx-modules/ngx_cache_purge/releases/tag/3.0.1
https://github.com/nginx-modules/ngx_cache_purge/releases/tag/3.0.2

3.0.0 is major release. Contains breaking internal changes.
Review the updated README before upgrading:
https://github.com/nginx-modules/ngx_cache_purge/blob/3.0.2/README.md

PR: 295591
Sponsored by: UNIS Labs
Co-authored-by: Vladimir Druzenko <vvd@FreeBSD.org>
MFH: 2026Q2

(cherry picked from commit c003955046a5e993107b0adbddb39be5e27074bc)