docs: add ngx-ratio-image (#2211)

Author: jdegand

README.md

@@ -1630,6 +1630,7 @@ Current Angular version: [![npm version](https://badge.fury.io/js/%40angular%2Fc
 * [unpic](https://unpic.pics/img/angular/) - Angular directive for responsive, high-performance images with automatic srcset, sizing, and CDN/CMS URL detection.
 * [ngx-image-fallback](https://github.com/joyblanks/ngx-image-fallback) - Image Fallback Directive for Angular.
 * [ng-image-optimizer](https://github.com/Hasan-Kakeh/ng-image-optimizer) - A high‑performance Angular SSR image optimizer that uses [Sharp](https://sharp.pixelplumbing.com/) to deliver a Next.js‑style experience.
+* [ngx-ratio-image](https://github.com/gerd-siebert/ngx-ratio-image) - Angular library for displaying an image with a variable aspect ratio inside a container with a fixed aspect ratio.
 
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