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/models/mailtemplate/columns.yaml

@@ -0,0 +1,23 @@
+# ===================================
+#  Column Definitions
+# ===================================
+
+columns:
+
+    code:
+        label: system::lang.mail_templates.code
+        searchable: true
+
+    subject:
+        label: system::lang.mail_templates.subject
+        searchable: true
+
+    description:
+        label: system::lang.mail_templates.description
+        searchable: true
+
+    layout:
+        label: system::lang.mail_templates.layout
+        relation: layout
+        select: name
+        sortable: false

modules/system/models/mailtemplate/fields.yaml

@@ -0,0 +1,45 @@
+# ===================================
+#  Field Definitions
+# ===================================
+
+fields:
+
+    layout:
+        label: system::lang.mail_templates.layout
+        type: relation
+        emptyOption: system::lang.mail_templates.no_layout
+
+    code:
+        label: system::lang.mail_templates.code
+        comment: system::lang.mail_templates.code_comment
+        span: left
+        context: create
+
+    subject@create:
+        label: system::lang.mail_templates.subject
+        comment: system::lang.mail_templates.subject_comment
+        span: right
+
+    subject@update:
+        label: system::lang.mail_templates.subject
+
+    description:
+        label: system::lang.mail_templates.description
+        type: textarea
+        size: tiny
+
+secondaryTabs:
+    fields:
+
+        content_html:
+            type: markdown
+            size: giant
+            tab: system::lang.mail_templates.content_html
+            safe: true
+            stretch: true
+
+        content_text:
+            type: textarea
+            size: giant
+            tab: system::lang.mail_templates.content_text
+            stretch: true