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/cms/assets/less/winter.theme-selector.less

@@ -0,0 +1,160 @@
+@import "../../../backend/assets/less/core/boot.less";
+
+.theme-selector-layout {
+    .layout-cell {
+        padding: 24px;
+        .box-sizing(border-box);
+    }
+
+    .theme-thumbnail {
+        width: 288px;
+        background: #ecf0f1;
+        border-top: 1px solid #e3e7e9;
+
+        img {
+            .opacity(0.6);
+            width: 240px;
+        }
+    }
+
+    .theme-description {
+        border-top: 1px solid #f2f3f4;
+
+        h3, p {
+            .opacity(0.6);
+        }
+
+        h3 {
+            margin: 0 0 25px 0;
+            font-size: 28px;
+            color: #2b3e50;
+            display: inline-block;
+        }
+
+        p.author {
+            font-size: 13px;
+            display: inline-block;
+            color: #808c8d;
+        }
+
+        p.description {
+            color: #2b3e50;
+            font-size: 14px;
+            line-height: 180%;
+            margin-bottom: 30px;
+        }
+
+        .controls {
+            .btn > i {
+                margin-right: 5px;
+                font-size: 16px;
+                position: relative;
+                top: 1px;
+
+                &.icon-star {
+                    color: #f1a84e;
+                }
+            }
+
+            .dropdown {
+                display: inline-block;
+            }
+        }
+    }
+
+    .layout-row.active {
+        .theme-thumbnail {
+            background: #bdc3c7;
+            border-top-color: #bdc3c7;
+       }
+
+       .thumbnail-container {
+            position: relative;
+
+            &:after {
+                .triangle(right, 15px, 28px, #bdc3c7);
+                position: absolute;
+                right: -35px;
+                top: 50%;
+                margin-top: -14px;
+            }
+       }
+    }
+
+    .layout-row {
+        &.active, &:hover {
+            .theme-description {
+                h3, p {
+                    .opacity(1);
+                }
+            }
+
+            .theme-thumbnail {
+                img {
+                    .opacity(1);
+                }
+            }
+        }
+
+        &:first-child, &.links {
+            .theme-description, .theme-thumbnail {
+                border-top: none;
+            }
+        }
+
+        &.links {
+            .theme-thumbnail {
+                border-bottom: 1px solid #e3e7e9;
+            }
+            .theme-description {
+                border-bottom: 1px solid #f2f3f4;
+            }
+        }
+    }
+
+    .create-new-theme {
+        margin-bottom: 10px;
+    }
+
+    .create-new-theme,
+    .find-more-themes {
+        background: #ecf0f1;
+        color: #2b3e50;
+        text-decoration: none;
+        display: block;
+        padding: 20px;
+        .border-radius(4px);
+
+        &:hover {
+            background: @link-color;
+            color: white;
+        }
+    }
+}
+
+//
+// Screen specific
+//
+
+@media (max-width: @screen-sm) {
+    .theme-selector-layout {
+        .layout-cell, .layout-row {
+            display: block!important;
+            width: auto!important;
+            height: auto!important;
+        }
+
+        .theme-thumbnail {
+            img {
+                width: 100%;
+            }
+        }
+
+        .layout-row.links {
+            .theme-thumbnail {
+                background: transparent;
+                padding: 0;
+            }
+        }
+    }
+}