fix: remove leading space from chat list row, aligning with header

The row started with ' ●' (space+fringe) but the header starts with
'  U' (two spaces).  Removing the extra space brings the row columns
in line with the header columns, matching the mockup.

noise-chat-list.el

@@ -109,7 +109,7 @@ CONV is a hash table with string keys from noise-db."
            (t (concat sender ": " preview))))
          (preview-str (truncate-string-to-width preview-prefix 36 nil nil "…"))
          (time-str (noise-chat-list--format-time timestamp)))
-    (concat " " (propertize fringe 'face 'warning) " " unread-str " "
+    (concat (propertize fringe 'face 'warning) " " unread-str " "
             (propertize (format "%-18s" name-str) 'face 'bold) "  "
             preview-str "  "
             (propertize time-str 'face 'shadow))))