feat(blog): add file-based blog with dynamic slugs, MDX content and layout shell

- Introduced blog routing using Next.js App Router
- Implemented dynamic [slug] pages for blog posts
- Added MDX-based content loading via lib/posts
- Integrated shared TopBar layout with navigation
- Established clear content, lib and component separation

apps/public-web/node_modules/autoprefixer/lib/old-value.js

@@ -0,0 +1,22 @@
+let utils = require('./utils')
+
+class OldValue {
+  constructor(unprefixed, prefixed, string, regexp) {
+    this.unprefixed = unprefixed
+    this.prefixed = prefixed
+    this.string = string || prefixed
+    this.regexp = regexp || utils.regexp(prefixed)
+  }
+
+  /**
+   * Check, that value contain old value
+   */
+  check(value) {
+    if (value.includes(this.string)) {
+      return !!value.match(this.regexp)
+    }
+    return false
+  }
+}
+
+module.exports = OldValue