fix(elisp): add lexical-binding comment to all files to suppress new Emacs 31 warnings

I've set `lexical-binding` to `nil` in all Emacs Lisp files to suppress
the warnings introduced in Emacs 31 requiring all elisp files to have a
`lexical-binding` comment.

This retains the default behavior of dynamic binding when no
`lexical-binding` comment is present. With it set to `t` across the
board, various things break, and fixing those is a task for another day.

modules/text-editing/siren-beginend.el

@@ -1,4 +1,4 @@
-;;; siren-beginend.el --- jimeh's Emacs Siren: beginend
+;;; siren-beginend.el --- jimeh's Emacs Siren: beginend  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-cycle-quotes.el

@@ -1,4 +1,4 @@
-;;; siren-cycle-quotes.el --- jimeh's Emacs Siren: cycle-quotes.
+;;; siren-cycle-quotes.el --- jimeh's Emacs Siren: cycle-quotes.  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-expand-region.el

@@ -1,4 +1,4 @@
-;;; siren-expand-region.el --- jimeh's Emacs Siren: expand-region
+;;; siren-expand-region.el --- jimeh's Emacs Siren: expand-region  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-goto-chg.el

@@ -1,4 +1,4 @@
-;;; siren-goto-chg.el --- jimeh's Emacs Siren: goto-chg configuration.
+;;; siren-goto-chg.el --- jimeh's Emacs Siren: goto-chg configuration.  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-ialign.el

@@ -1,4 +1,4 @@
-;;; siren-ialign.el --- jimeh's Emacs Siren: ialign
+;;; siren-ialign.el --- jimeh's Emacs Siren: ialign  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-insert.el

@@ -1,4 +1,4 @@
-;;; siren-insert.el --- jimeh's Emacs Siren: misc text insert functions
+;;; siren-insert.el --- jimeh's Emacs Siren: misc text insert functions  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-move-dup.el

@@ -1,4 +1,4 @@
-;;; siren-move-dup.el --- jimeh's Emacs Siren: move-dup
+;;; siren-move-dup.el --- jimeh's Emacs Siren: move-dup  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-multiple-cursors.el

@@ -1,4 +1,4 @@
-;;; siren-multiple-cursors.el --- jimeh's Emacs Siren: multiple-cursors configuration.
+;;; siren-multiple-cursors.el --- jimeh's Emacs Siren: multiple-cursors configuration.  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-randomize-region.el

@@ -1,4 +1,4 @@
-;;; siren-randomize-region.el --- jimeh's Emacs Siren: randomize-region
+;;; siren-randomize-region.el --- jimeh's Emacs Siren: randomize-region  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-safe-change-case.el

@@ -1,4 +1,4 @@
-;;; siren-safe-change-case.el --- jimeh's Emacs Siren: change-case
+;;; siren-safe-change-case.el --- jimeh's Emacs Siren: change-case  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-shift-number.el

@@ -1,4 +1,4 @@
-;;; siren-shift-number.el --- jimeh's Emacs Siren: shift-number.
+;;; siren-shift-number.el --- jimeh's Emacs Siren: shift-number.  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-shift-text.el

@@ -1,4 +1,4 @@
-;;; siren-shift-text.el --- jimeh's Emacs Siren: shift-text
+;;; siren-shift-text.el --- jimeh's Emacs Siren: shift-text  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-smart-shift.el

@@ -1,4 +1,4 @@
-;;; siren-smart-shift.el --- jimeh's Emacs Siren: smart-shift
+;;; siren-smart-shift.el --- jimeh's Emacs Siren: smart-shift  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-smartparens.el

@@ -1,4 +1,4 @@
-;;; siren-smartparens.el --- jimeh's Emacs Siren: smartparens configuration.
+;;; siren-smartparens.el --- jimeh's Emacs Siren: smartparens configuration.  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-sort-symbols.el

@@ -1,4 +1,4 @@
-;;; siren-sort-symbols.el --- jimeh's Emacs Siren: sort-symbols.
+;;; siren-sort-symbols.el --- jimeh's Emacs Siren: sort-symbols.  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-sort-words.el

@@ -1,4 +1,4 @@
-;;; siren-sort-words.el --- jimeh's Emacs Siren: sort-words.
+;;; siren-sort-words.el --- jimeh's Emacs Siren: sort-words.  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-string-edit.el

@@ -1,4 +1,4 @@
-;;; siren-string-edit.el --- jimeh's Emacs Siren: defaults for string-edit
+;;; siren-string-edit.el --- jimeh's Emacs Siren: defaults for string-edit  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-string-inflection.el

@@ -1,4 +1,4 @@
-;;; siren-string-inflection.el --- jimeh's Emacs Siren: defaults for string-inflection
+;;; siren-string-inflection.el --- jimeh's Emacs Siren: defaults for string-inflection  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-tempel.el

@@ -1,4 +1,4 @@
-;;; siren-tempel.el --- jimeh's Emacs Siren: tempel configuration.
+;;; siren-tempel.el --- jimeh's Emacs Siren: tempel configuration.  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-toggle-comments.el

@@ -1,4 +1,4 @@
-;;; siren-toggle-comments.el --- jimeh's Emacs Siren: toggle-comments
+;;; siren-toggle-comments.el --- jimeh's Emacs Siren: toggle-comments  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-toggle-quotes.el

@@ -1,4 +1,4 @@
-;;; siren-toggle-quotes.el --- jimeh's Emacs Siren: toggle-quotes.
+;;; siren-toggle-quotes.el --- jimeh's Emacs Siren: toggle-quotes.  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-tree-sitter.el

@@ -1,4 +1,4 @@
-;;; siren-tree-sitter.el --- jimeh's Emacs Siren: tree-sitter
+;;; siren-tree-sitter.el --- jimeh's Emacs Siren: tree-sitter  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-treesit.el

@@ -1,4 +1,4 @@
-;;; siren-treesit.el --- jimeh's Emacs Siren: treesit
+;;; siren-treesit.el --- jimeh's Emacs Siren: treesit  -*- lexical-binding: nil; -*-
 
 ;;; Commentary:
 

modules/text-editing/siren-yasnippet.el

@@ -1,4 +1,4 @@
-;;; siren-yasnippet.el --- jimeh's Emacs Siren: yasnippet configuration.
+;;; siren-yasnippet.el --- jimeh's Emacs Siren: yasnippet configuration.  -*- lexical-binding: nil; -*-
 
 ;;; Commentary: