Add: Announcement post for 15.1 (#373)

Co-authored-by: Michael Lutz <michi@icosahedron.de>

Author: 2TallTyler

_posts/2026-01-24-openttd-15-1.md

@@ -0,0 +1,19 @@
+---
+title: OpenTTD 15.1
+author: 2TallTyler
+---
+
+Brr, it's cold out, especially in the subarctic climate where we've been testing some snowy bugfixes.
+
+Yes, it's time for a bug fixing release, OpenTTD 15.1. The list of fixes include:
+
+* Trees grow on partially-snowy tiles again
+* Town cargo graphs show correct dates
+* The online content list no longer loses name and version at some font sizes
+* A variety of other bugfixes, including a critical security fix; see the full changelog for more details
+
+If you find any more bugs, please [report them here](https://github.com/OpenTTD/OpenTTD/issues/new/choose).
+
+* [Download](https://www.openttd.org/downloads/openttd-releases/latest.html)
+* [Changelog](https://cdn.openttd.org/openttd-releases/15.1/changelog.md)
+* [Bug tracker](https://github.com/OpenTTD/OpenTTD/issues)