Add part 2 of CGP Ext Types article

Author: mariannegoldin

draft/2025-07-09-this-week-in-rust.md

@@ -56,7 +56,7 @@ and just ask the editors to select the category.
 * [Tree-Structured Concurrency II: Replacing Background Tasks With Actors](https://blog.yoshuawuyts.com/replacing-tasks-with-actors/)
 * [Rapid Machine Learning Prototyping in Rust](https://ryuru.com/rapid-machine-learning-prototyping-in-rust/)
 * [330× faster: Four different ways to speed up your code](https://pythonspeed.com/articles/different-ways-speed/)
-* [Programming Extensible Data Types in Rust with CGP - Part 1: Modular App Construction and Extensible Builders](https://contextgeneric.dev/blog/extensible-datatypes-part-1/)
+* [Programming Extensible Data Types in Rust with CGP, Part 1](https://contextgeneric.dev/blog/extensible-datatypes-part-1/) and [Part 2](https://contextgeneric.dev/blog/extensible-datatypes-part-2/)
 * [Making Unsafe Rust a Little Safer: Find Memory Errors in Production with GWP-ASan](https://blog.colinbreck.com/making-unsafe-rust-a-little-safer-find-memory-errors-in-production-with-gwp-asan/)
 * [Deterministic Simulation Testing in Rust: A Theater Of State Machines](https://www.polarsignals.com/blog/posts/2025/07/08/dst-rust)
 * [Slint Material Components Tech Preview](https://slint.dev/blog/material-comp-tech-preview)