fix header line

Author: jcs090218

chatgpt.el

@@ -354,7 +354,7 @@ The data is consist of ROLE and CONTENT."
 
 (defun chatgpt-input-header-line ()
   "The display for input header line."
-  (format "Session: %s" (cdr chatgpt-input-instance)))
+  (format " Session: %s" (cdr chatgpt-input-instance)))
 
 (defvar chatgpt-input-mode-map
   (let ((map (make-sparse-keymap)))
@@ -423,9 +423,10 @@ The data is consist of ROLE and CONTENT."
 
 (defun chatgpt-header-line ()
   "The display for header line."
-  ;; TODO: ..
-  ""
-  )
+  (format " Session: %s, History: %s, User: %s (M-x chatgpt-info)"
+          (cdr chatgpt-instance)
+          (length chatgpt-chat-history)
+          (chatgpt-user)))
 
 (defvar chatgpt-mode-map
   (let ((map (make-sparse-keymap)))