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/gray-matter/lib/to-file.js

@@ -0,0 +1,43 @@
+'use strict';
+
+const typeOf = require('kind-of');
+const stringify = require('./stringify');
+const utils = require('./utils');
+
+/**
+ * Normalize the given value to ensure an object is returned
+ * with the expected properties.
+ */
+
+module.exports = function(file) {
+  if (typeOf(file) !== 'object') {
+    file = { content: file };
+  }
+
+  if (typeOf(file.data) !== 'object') {
+    file.data = {};
+  }
+
+  // if file was passed as an object, ensure that
+  // "file.content" is set
+  if (file.contents && file.content == null) {
+    file.content = file.contents;
+  }
+
+  // set non-enumerable properties on the file object
+  utils.define(file, 'orig', utils.toBuffer(file.content));
+  utils.define(file, 'language', file.language || '');
+  utils.define(file, 'matter', file.matter || '');
+  utils.define(file, 'stringify', function(data, options) {
+    if (options && options.language) {
+      file.language = options.language;
+    }
+    return stringify(file, data, options);
+  });
+
+  // strip BOM and ensure that "file.content" is a string
+  file.content = utils.toString(file.content);
+  file.isEmpty = false;
+  file.excerpt = '';
+  return file;
+};