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/static-env.d.ts

@@ -0,0 +1,13 @@
+import type { NextConfigComplete, NextConfigRuntime } from '../server/config-shared';
+/**
+ * Collects all environment variables that are using the `NEXT_PUBLIC_` prefix.
+ */
+export declare function getNextPublicEnvironmentVariables(): {
+    [k: string]: string | undefined;
+};
+/**
+ * Collects the `env` config value from the Next.js config.
+ */
+export declare function getNextConfigEnv(config: NextConfigComplete | NextConfigRuntime): Record<string, string | undefined>;
+export declare function getStaticEnv(config: NextConfigComplete | NextConfigRuntime, deploymentId: string): Record<string, string | undefined>;
+export declare function populateStaticEnv(config: NextConfigComplete | NextConfigRuntime, deploymentId: string): void;