style(lists): replace '— ' dash prefix with vertical gold bar accent

The em-dash prefix on list items felt typographic but unbranded. Now each
list item gets a 3px-wide gold vertical bar on the left, evoking a tactical
breadcrumb. Implementation :
- Builders (av_build_list_section in _av-bricks-shared.php +
  av_build_form_two_col promise list in av-generate-forms.php) emit clean
  text without the '— ' prefix, and set _cssClasses = 'av-list-item'
- New mu-plugin av-list-bullet-style.php injects CSS via wp_head() :
  .av-list-item { position: relative; padding-left: 0.9rem; }
  .av-list-item::before { gold bar, 3px × 1.1em, aligned to first line }

Regen all sections (industries, solutions, technology, editorial, forms,
home) to switch existing pages to the new style.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tools/_av-bricks-shared.php

@@ -418,7 +418,8 @@ function av_build_list_section($slug, $i, $section, $bg = 'var(--color-bg-defaul
         $els[] = [
             'id' => "i{$slug}l{$i}x{$j}", 'name' => 'text-basic', 'parent' => $list, 'children' => [],
             'settings' => [
-                'text' => '— ' . $item,
+                'text' => $item,                                // no "— " prefix anymore
+                '_cssClasses' => 'av-list-item',                // gold-bar accent via wp_head CSS
                 '_typography' => [
                     'color'       => av_color('var(--color-text-secondary)'),
                     'font-size'   => '1rem',