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/tests/fixtures/plugins/winter/tester/Plugin.php

@@ -0,0 +1,74 @@
+<?php namespace Winter\Tester;
+
+use System\Classes\PluginBase;
+
+class Plugin extends PluginBase
+{
+    public function pluginDetails()
+    {
+        return [
+            'name' => 'Winter Test Plugin',
+            'description' => 'Test plugin used by unit tests.',
+            'author' => 'Alexey Bobkov, Samuel Georges'
+        ];
+    }
+
+    public function registerComponents()
+    {
+        return [
+            'Winter\Tester\Components\Archive' => 'testArchive',
+            'Winter\Tester\Components\Post' => 'testPost',
+            'Winter\Tester\Components\MainMenu' => 'testMainMenu',
+            'Winter\Tester\Components\ContentBlock' => 'testContentBlock',
+            'Winter\Tester\Components\Comments' => 'testComments',
+        ];
+    }
+
+    public function registerFormWidgets()
+    {
+        return [
+            'Winter\Tester\FormWidgets\Preview' => [
+                'label' => 'Preview',
+                'code'  => 'preview'
+            ]
+        ];
+    }
+
+    public function registerNavigation()
+    {
+        return [
+            'blog' => [
+                'label'       => 'Blog',
+                'url'         => 'http://example.com/blog/posts',
+                'icon'        => 'icon-pencil',
+                'permissions' => ['winter.blog.*'],
+                'order'       => 500,
+
+                'sideMenu' => [
+                    'posts' => [
+                        'label'       => 'Posts',
+                        'icon'        => 'icon-copy',
+                        'url'         => 'http://example.com/blog/posts',
+                        'permissions' => ['winter.blog.access_posts']
+                    ],
+                    'categories' => [
+                        'label'       => 'Categories',
+                        'icon'        => 'icon-list-ul',
+                        'url'         => 'http://example.com/blog/categories',
+                        'permissions' => ['winter.blog.access_categories']
+                    ],
+                ]
+            ]
+        ];
+    }
+
+    public function registerValidationRules()
+    {
+        return [
+            'uppercase' => function ($attribute, $value, $parameters, $validator) {
+                return strtoupper($value) === $value;
+            },
+            'be_like_bob' => \Winter\Tester\Rules\BeLikeBobRule::class,
+        ];
+    }
+}