_content/blog: add Go 1.25 release post

This post tries to be short. It lets readers know that Go 1.25 is out,
and as much as possible directs them to read the Go 1.25 Release Notes
to see what's new. That document is where we've invested most of the
effort of documenting and highlighting the Go 1.25 release changes,
so the blog post can mostly link to it.

It was tempting to try and include a subset of highlights, but it's
tricky to do that without either making it seem like it's a complete
list (when it's not), or making the post too long and harder to see
parts of it that that aren't already in scope of the release notes.

Balance this out by picking a handful of interesting features to
highlight in the blog post summary (where it's clear that it's not
the full list), and by enumerating experimental additions that would
benefit from early testing.

Change-Id: Iaca7c3a638a00a406e230306a0bff741c909a06e
Reviewed-on: https://go-review.googlesource.com/c/website/+/694835
Reviewed-by: David Chase <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>
Reviewed-by: Austin Clements <[email protected]>
TryBot-Bypass: Dmitri Shuralyov <[email protected]>

Author: dmitshur

_content/blog/go1.25.md

@@ -0,0 +1,40 @@
+---
+title: Go 1.25 is released
+date: 2025-08-12
+by:
+- Dmitri Shuralyov, on behalf of the Go team
+summary: Go 1.25 adds container-aware GOMAXPROCS, testing/synctest package, experimental GC, experimental encoding/json/v2, and more.
+---
+
+Today the Go team is pleased to release Go 1.25.
+You can find its binary archives and installers on the [download page](/dl/).
+
+Go 1.25 comes with improvements over Go 1.24 across
+its [tools](/doc/go1.25#tools),
+the [runtime](/doc/go1.25#runtime),
+[compiler](/doc/go1.25#compiler),
+[linker](/doc/go1.25#linker),
+and the [standard library](/doc/go1.25#library),
+including the addition of one [new package](/doc/go1.25#new-testingsynctest-package).
+There are [port-specific](/doc/go1.25#ports) changes
+and [`GODEBUG` settings](/doc/godebug#go-125) updates.
+
+Some of the additions in Go 1.25 are in an experimental stage
+and become exposed only when you explicitly opt in.
+Notably, a [new experimental garbage collector](/doc/go1.25#new-experimental-garbage-collector),
+and a [new experimental `encoding/json/v2` package](/doc/go1.25#json_v2)
+are available for you to try ahead of time and provide your feedback.
+It really helps if you're able to do that!
+
+Please refer to the [Go 1.25 Release Notes](/doc/go1.25) for the complete list
+of additions, changes and improvements in Go 1.25.
+
+Over the next few weeks, follow-up blog posts will cover some of the topics
+relevant to Go 1.25 in more detail. Check back in later to read those posts.
+
+Thanks to everyone who contributed to this release by writing code, filing bugs,
+trying out experimental additions, sharing feedback, and testing the release candidates.
+Your efforts helped make Go 1.25 as stable as possible.
+As always, if you notice any problems, please [file an issue](/issue/new).
+
+We hope you enjoy using the new release!