feat(mu4e): signature from ~/.mail/signature file

config.el

@@ -656,6 +656,10 @@ and optional priority indicator [#A]."
   ;; Do not cite sender's signature in replies
   (setq message-cite-function #'message-cite-original-without-signature)
 
+  ;; Signature from file — create ~/.mail/signature with your sig text
+  (setq message-signature-file (expand-file-name "~/.mail/signature")
+        message-signature t)
+
   ;; Move cursor past headers to message body when opening a message
   ;; Modern mu4e (1.8+) uses gnus-article-mode, not mu4e-view-mode.
   ;; We use mu4e-view-rendered-hook which fires after the message is displayed,

signature.example

@@ -0,0 +1,6 @@
+--
+Martin Sukany
+IT Architect
+E: martin@sukany.cz
+W: https://sukany.cz
+Note: This message was sent with help of Daneel, my personal AI assistant.