Add `Rust compiler performance survey 2025 results` blog post by Kobzol · Pull Request #6999 · rust-lang/this-week-in-rust

The end of the year is a time for reflection, so I thought that I should take a look back at the previous year. And since my main job is currently contributing to open-source, what better way to do that than enumerating all the Rust pull requests that I opened in 2025. In this post, I’ll share stats about my Rust contributions from the past year and also some thoughts about open-source (Rust) maintenance, as this topic is highly relevant right now.