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/next/dist/lib/metadata/get-metadata-route.d.ts

@@ -0,0 +1,19 @@
+/**
+ * Fill the dynamic segment in the metadata route
+ *
+ * Example:
+ * fillMetadataSegment('/a/[slug]', { params: { slug: 'b' } }, 'open-graph') -> '/a/b/open-graph'
+ *
+ */
+export declare function fillMetadataSegment(segment: string, params: any, lastSegment: string): string;
+/**
+ * Map metadata page key to the corresponding route
+ *
+ * static file page key:    /app/robots.txt -> /robots.xml -> /robots.txt/route
+ * dynamic route page key:  /app/robots.tsx -> /robots -> /robots.txt/route
+ *
+ * @param page
+ * @returns
+ */
+export declare function normalizeMetadataRoute(page: string): string;
+export declare function normalizeMetadataPageToRoute(page: string, isDynamic: boolean): string;