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/views/mail/invite.php

@@ -0,0 +1,20 @@
+subject = "Welcome to {{ appName | raw }}"
+layout = "system"
+description = "Invite new admin to the site"
+==
+Hi {{ name }}
+
+A user account has been created for you on **{{ appName }}**.
+
+{% partial 'panel' body %}
+- Login: `{{ login ?: 'sample' }}`
+- Password: `{{ (password ?: '********') | raw }}`
+{% endpartial %}
+
+You can use the following link to sign in:
+
+{% partial 'button' url=link body %}
+    Sign in to admin area
+{% endpartial %}
+
+After signing in you should change your password by clicking your name on the top right corner of the administration area.

modules/backend/views/mail/restore.php

@@ -0,0 +1,13 @@
+subject = "Password Reset"
+layout = "system"
+description = "Reset an admin password"
+==
+Hello {{ name }}
+
+Somebody has requested a password reset for your account, if this was not you, please ignore this email.
+
+You can use the following link to restore your password:
+
+{% partial 'button' url=link type='positive' body %}
+Restore password
+{% endpartial %}