docs: Add onboarding video

Author: igorlukanin

docs/pages/product/introduction.mdx

@@ -6,6 +6,11 @@ Cube is the [agentic analytics](#agentic-analytics) platform built on top of the
 
 Cube enables AI agents and users to query, explore, and manipulate data models — transforming the semantic layer into a dynamic, governed workspace for generating insights, automating workflows, and building data products.
 
+<YouTubeVideo
+  url="https://www.youtube.com/embed/n-U1FvHqE2Q"
+  aspectRatio={16/10}
+/>
+
 Cube is a new generation of a BI platform built to be used by both humans and AI agents. It empowers different personas across your organization:
 
 - **Data Engineers** can quickly curate data models with AI assistance, accelerating the development and maintenance of semantic layers