add description for architecture

Author: nidhi-singh02

pages/price-feeds/pro/how-lazer-works.mdx

@@ -5,6 +5,8 @@ It aggregates data from multiple publishers and distributes it to consumers thro
 
 ## Architecture Diagram
 
+The following diagram illustrates the data flow from publishers through relayers and message queues to routers that aggregate prices and serve consumers, with history services providing persistence and governance managing system configuration.
+
 ![Pyth Pro Architecture](../../../images/lazer/Pyth_Pro_Architecture.svg)
 
 ## System Services