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/build/handle-externals.d.ts

@@ -0,0 +1,19 @@
+import type { WebpackLayerName } from '../lib/constants';
+import type { NextConfigComplete } from '../server/config-shared';
+import type { ResolveOptions } from 'webpack';
+export declare function isResourceInPackages(resource: string, packageNames?: string[], packageDirMapping?: Map<string, string>): boolean;
+export declare function resolveExternal(dir: string, esmExternalsConfig: NextConfigComplete['experimental']['esmExternals'], context: string, request: string, isEsmRequested: boolean, getResolve: (options: ResolveOptions) => (resolveContext: string, resolveRequest: string) => Promise<[string | null, boolean]>, isLocalCallback?: (res: string) => any, baseResolveCheck?: boolean, esmResolveOptions?: any, nodeResolveOptions?: any, baseEsmResolveOptions?: any, baseResolveOptions?: any): Promise<{
+    localRes: any;
+    res?: undefined;
+    isEsm?: undefined;
+} | {
+    res: string | null;
+    isEsm: boolean;
+    localRes?: undefined;
+}>;
+export declare function makeExternalHandler({ config, optOutBundlingPackageRegex, transpiledPackages, dir, }: {
+    config: NextConfigComplete;
+    optOutBundlingPackageRegex: RegExp;
+    transpiledPackages: string[];
+    dir: string;
+}): (context: string, request: string, dependencyType: string, layer: WebpackLayerName | null, getResolve: (options: any) => (resolveContext: string, resolveRequest: string) => Promise<[string | null, boolean]>) => Promise<any>;