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/system/console/scaffold/settings/fields.stub

@@ -0,0 +1,7 @@
+# ===================================
+#  Form Field Definitions
+# ===================================
+
+fields:
+    settings_option:
+        label: This is a sample settings field used by {{author}}.{{plugin}}

modules/system/console/scaffold/settings/model.stub

@@ -0,0 +1,33 @@
+<?php
+
+namespace {{ plugin_namespace }}\Models;
+
+use Model;
+
+/**
+ * {{name}} Model
+ */
+class {{studly_name}} extends Model
+{
+    use \Winter\Storm\Database\Traits\Validation;
+
+    /**
+     * @var array Behaviors implemented by this model.
+     */
+    public $implement = [\System\Behaviors\SettingsModel::class];
+
+    /**
+     * @var string Unique code
+     */
+    public $settingsCode = '{{lower_author}}_{{lower_plugin}}_{{lower_name}}';
+
+    /**
+     * @var mixed Settings form field definitions
+     */
+    public $settingsFields = 'fields.yaml';
+
+    /**
+     * @var array Validation rules
+     */
+    public $rules = [];
+}