doc/next: pre-announce end of support for macOS 12 in Go 1.27

For #75836

Change-Id: I7fd515eb7fcdfb5944388ab42716fd81bc13a7b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/723080
Reviewed-by: Cherry Mui <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>

Author: seankhliao

doc/next/7-ports.md

@@ -1,6 +1,13 @@
 ## Ports {#ports}
 
+### Darwin
+
+<!-- go.dev/issue/75836 -->
+
+Go 1.26 is the last release that will run on macOS 12 Monterey. Go 1.27 will require macOS 13 Ventura or later.
+
 ### Windows
 
 <!-- go.dev/issue/71671 -->
+
 As [announced](/doc/go1.25#windows) in the Go 1.25 release notes, the [broken](/doc/go1.24#windows) 32-bit windows/arm port (`GOOS=windows` `GOARCH=arm`) is removed.