doc: update copyright years to 2026 and add missing author field

Update copyright headers across all 37 .el files to include 2026.
Add missing Author field to testutil-wttrin.el for consistency.

1 files changed, 1 insertions, 1 deletions

diff --git a/wttrin.el b/wttrin.el
index d4726ab..c93aae2 100644
--- a/wttrin.el
+++ b/wttrin.el
@@ -1,6 +1,6 @@
 ;;; wttrin.el --- Emacs Frontend for Service wttr.in -*- lexical-binding: t; coding: utf-8; -*-
 ;;
-;; Copyright (C) 2024 Craig Jennings
+;; Copyright (C) 2024-2026 Craig Jennings
 ;; Maintainer: Craig Jennings <c@cjennings.net>
 ;;
 ;; Original Authors: Carl X. Su <bcbcarl@gmail.com>