Add backup performance changelog

src/routes/changelog/(entries)/2025-03-21.markdoc

@@ -0,0 +1,19 @@
+---
+layout: changelog
+title: Backup performance improved by over 700%
+date: 2025-03-21
+---
+
+Appwrite Cloud backups are now significantly faster, reducing wait times and improving reliability.
+
+## What's improved
+
+- **Backup creation** is **7x faster** (from **241.3s** → **29.1s**)
+- **Backup archiving** is nearly **3x faster** (from **5.8s** → **1.5s**)
+- **Overall backup process** is **7x faster** (from **247.1s** → **30.6s**)
+
+This optimization drastically cuts down backup times, making data recovery and management more efficient.
+
+{% arrow_link href="/docs/products/databases/backups" %}
+Learn more about backups
+{% /arrow_link %}