Add wireguard-tools v1.0.20260223 to rocky9

Build the wg and wg-quick CLI from the upstream tag snapshot; only the
rocky9 image builds it for now.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

fetch-sources.sh

@@ -164,3 +164,5 @@ fetch ThreadPool-cc0b6371d3963f7028c2da5fc007733f9f3bf205.tar.gz \
     https://wangguofang.net/github.com/log4cplus/ThreadPool/archive/cc0b6371d3963f7028c2da5fc007733f9f3bf205.tar.gz
 fetch sqlite-autoconf-3540100.tar.gz \
     https://www.sqlite.org/2026/sqlite-autoconf-3540100.tar.gz
+fetch wireguard-tools-v1.0.20260223.tar.xz \
+    https://git.zx2c4.com/wireguard-tools/snapshot/wireguard-tools-v1.0.20260223.tar.xz