Update scsh file headers for shell scripts

Other file headers come with caveats:

- ‘#!/usr/bin/scsh -s’ :: Now that scsh is installed through Guix, this is not
  where this file lives.

- ‘#!/usr/bin/env -S scsh -s’ :: This doesn't work when we need to specify move
  arguments on the command line and need to use the meta-argument.
  ‘env -S scsh \’ doesn't work.

herbstluftwm/usr/bin/hlwm-run-or-raise

@@ -1,4 +1,7 @@
-#!/usr/bin/scsh -s
+#!/usr/bin/env sh
+# # -*- mode: scheme; -*-
+IFS=" "
+exec scsh -s "$0" "$@"
 !#
 ;; hlwm-run-or-raise --- Raise a window or start a new process
 ;;

herbstluftwm/usr/bin/hlwm-switch-tags

@@ -1,5 +1,7 @@
-#!/usr/bin/scsh \
--o define-record-types -s
+#!/usr/bin/env sh
+# -*- mode: scheme; -*-
+IFS=" "
+exec scsh -o define-record-types -s "$0" "$@"
 !#
 ;; hlwm-switch-tags --- Switch the currently visible tags
 ;;

polybar/usr/bin/count-emails

@@ -1,5 +1,7 @@
-#!/usr/bin/env -S scsh -s
-;; -*- mode: scheme; -*-
+#!/usr/bin/env sh
+# -*- mode: scheme; -*-
+IFS=" "
+exec scsh -s "$0" "$@"
 !#
 
 (define mail-root (string-append (getenv "HOME") "/documents/mail"))