feat: Update Dockerfile for Node 20 and add vite-env.d.ts for environment variables

vite-env.d.ts

@@ -0,0 +1,24 @@
+/// <reference types="vite/client" />
+
+declare module '*.css';
+declare module '*.scss';
+declare module '*.png';
+declare module '*.jpg';
+declare module '*.jpeg';
+declare module '*.svg';
+declare module '*.mjs';
+declare module 'pdfjs-dist/build/pdf.worker.mjs?url';
+
+interface ImportMetaEnv {
+  readonly VITE_API_URL?: string;
+  readonly VITE_LINK_TO_GITHUB?: string;
+  readonly VITE_LINK_TO_LINKEDIN?: string;
+  readonly VITE_IP_Server?: string;
+  readonly VITE_MAIL?: string;
+  readonly VITE_NAME?: string;
+  // add other env vars here as needed
+}
+
+interface ImportMeta {
+  readonly env: ImportMetaEnv;
+}