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/env/dist/index.d.ts

@@ -0,0 +1,22 @@
+export type Env = {
+    [key: string]: string | undefined;
+};
+export type LoadedEnvFiles = Array<{
+    path: string;
+    contents: string;
+    env: Env;
+}>;
+export declare let initialEnv: Env | undefined;
+export declare function updateInitialEnv(newEnv: Env): void;
+type Log = {
+    info: (...args: any[]) => void;
+    error: (...args: any[]) => void;
+};
+export declare function processEnv(loadedEnvFiles: LoadedEnvFiles, dir?: string, log?: Log, forceReload?: boolean, onReload?: (envFilePath: string) => void): Env[];
+export declare function resetEnv(): void;
+export declare function loadEnvConfig(dir: string, dev?: boolean, log?: Log, forceReload?: boolean, onReload?: (envFilePath: string) => void): {
+    combinedEnv: Env;
+    parsedEnv: Env | undefined;
+    loadedEnvFiles: LoadedEnvFiles;
+};
+export {};