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

themes/demo/partials/explain/ajax.htm

@@ -0,0 +1,65 @@
+<hr />
+
+<!-- This file is an explanation of the AJAX page -->
+
+<p class="lead">
+    <i class="icon-copy"></i> &nbsp; The HTML markup for this example:
+</p>
+
+<pre>{% apply escape %}<!-- The form -->
+<form role="form" data-request="onTest" data-request-update="calcresult: '#result'">
+    <input type="text" value="15" name="value1">
+    <select name="operation">
+        <option>+</option>
+        <option>-</option>
+        <option>*</option>
+        <option>/</option>
+    </select>
+    <input type="text" value="5" name="value2">
+    <button type="submit">Calculate</button>
+</form>
+
+<!-- The result -->
+<div id="result">{{ "{% partial \"calcresult\" %}" }}</div>
+{% endapply %}</pre>
+
+<hr />
+
+<p class="lead">
+    <i class="icon-tags"></i> &nbsp; The <code>calcresult</code> partial:
+</p>
+
+<pre>{% apply escape %}
+{{ "{% if result %}" }}
+    The result is {{ "{{ result }}" }}.
+{{ "{% else %}" }}
+    Click the <em>Calculate</em> button to find the answer.
+{{ "{% endif %}" }}{% endapply %}</pre>
+
+<hr />
+
+<p class="lead">
+    <i class="icon-code"></i> &nbsp; The <code>onTest</code> PHP code:
+</p>
+
+<pre>function onTest()
+{
+    $value1 = input('value1');
+    $value2 = input('value2');
+    $operation = input('operation');
+
+    switch ($operation) {
+        case '+' :
+            $this['result'] = $value1 + $value2;
+            break;
+        case '-' :
+            $this['result'] = $value1 - $value2;
+            break;
+        case '*' :
+            $this['result'] = $value1 * $value2;
+            break;
+        default :
+            $this['result'] = $value1 / $value2;
+            break;
+    }
+}</pre>

themes/demo/partials/explain/plugins.htm

@@ -0,0 +1,17 @@
+<hr />
+
+<p class="lead">
+    <i class="icon-copy"></i> &nbsp; The HTML markup for this example:
+</p>
+<pre>
+{% apply escape %}
+{{ "{% component 'demoTodo' %}" }}
+{% endapply %}</pre>
+
+<hr />
+
+<p class="lead">
+    <i class="icon-question"></i> &nbsp; Wait, only one line is needed?
+</p>
+<p><em>Yes!</em> unlike the <a href="{{ 'ajax'|page }}">AJAX example</a>, components are simple building blocks that can be used with a small amount of code.</p>
+<p>The <code>demoTodo</code> component used here is provided by the plugin called <strong>Winter\Demo</strong>, you can find it in the <code>plugins/winter/demo</code> folder.</p>