feat: VivesPOS landing on Winter CMS 1.2 — theme + plugin + Dockerfile

- Base: wintercms/winter branch 1.2 (full framework)
- Theme vivespos: Canvas 7 + Bootstrap 5 CDN, custom CSS
- Layout: deferred GTM/GA4 tracking, JSON-LD SoftwareApplication
- Partials: hero (offline-first), features, modes (offline/nube toggle),
  screenshots, pricing (3 planes), comparison, FAQ, CTA
- Plugin VivesPOS.Site with ContactForm
- Dockerfile: PHP 8.2 Apache, port 80, healthcheck
- Added winter/wn-pages, blog, sitemap, seo plugins
- Active theme set to vivespos

modules/backend/controllers/preferences/_example_code.php

@@ -0,0 +1,24 @@
+form, fieldset, h5, h6, pre, blockquote, ol, dl, dt, dd, address, dd, dtm, div, td, th, hr {
+    margin: 0;
+    padding: 0;
+}
+
+/* This is a comment */
+body {
+    background-color: white;
+    font: 62.5% Helvetica, Arial, Tahoma, Verdana, Helvetica, sans-serif;
+}
+
+p {
+    font-size: 12px;
+}
+
+strong {
+    font-weight: bold;
+}
+
+span.alert {
+    color: #ff0000;
+    border: 1px solid #ff0000;
+    padding: 2rem;
+}