feat: Simple Mode language routing and translation improvements

## Simple Mode Enhancements
- Add `simple-index.html` as dedicated homepage for Simple Mode
- Hide marketing sections (FAQ, How It Works, Related Tools) on tool pages
- Add simplified navbar and footer for tool pages in Simple Mode
- Configure vite preview server to handle language-prefixed URLs

## Language Routing
- Add middleware to rewrite language-prefixed URLs (e.g., /de/merge-pdf.html)
- Support all languages: en, de, es, fr, id, it, pt, tr, vi, zh, zh-TW
- Create .htaccess with internal rewrites for Apache/Hostinger hosting

## Translation Updates
- Add missing translations for digitalSignPdf, validateSignaturePdf,
  emailToPdf, fontToOutline, deskewPdf to es, pt, tr, zh-TW
- Add Digital Signature and Validate Signature to homepage translation keys
- Fix language regex patterns to include all supported languages
- Fix typo in encrypt-pdf.html

src/js/i18n/i18n.ts

@@ -14,6 +14,7 @@ export const supportedLanguages = [
   'tr',
   'id',
   'it',
+  'pt',
 ] as const;
 export type SupportedLanguage = (typeof supportedLanguages)[number];
 
@@ -23,17 +24,20 @@ export const languageNames: Record<SupportedLanguage, string> = {
   de: 'Deutsch',
   es: 'Español',
   zh: '中文',
-  "zh-TW": '繁體中文（台灣）',
+  'zh-TW': '繁體中文（台灣）',
   vi: 'Tiếng Việt',
   tr: 'Türkçe',
   id: 'Bahasa Indonesia',
   it: 'Italiano',
+  pt: 'Português',
 };
 
 export const getLanguageFromUrl = (): SupportedLanguage => {
   const path = window.location.pathname;
 
-  const langMatch = path.match(/^\/(en|fr|es|de|zh|zh-TW|vi|tr|id|it)(?:\/|$)/);
+  const langMatch = path.match(
+    /^\/(en|fr|es|de|zh|zh-TW|vi|tr|id|it|pt)(?:\/|$)/
+  );
   if (
     langMatch &&
     supportedLanguages.includes(langMatch[1] as SupportedLanguage)
@@ -95,9 +99,12 @@ export const changeLanguage = (lang: SupportedLanguage): void => {
   const currentLang = getLanguageFromUrl();
 
   let newPath: string;
-  if (currentPath.match(/^\/(en|fr|de|zh|zh-TW|vi|tr|id|it)\//)) {
-    newPath = currentPath.replace(/^\/(en|fr|de|zh|zh-TW|vi|tr|id|it)\//, `/${lang}/`);
-  } else if (currentPath.match(/^\/(en|fr|de|zh|zh-TW|vi|tr|id|it)$/)) {
+  if (currentPath.match(/^\/(en|fr|es|de|zh|zh-TW|vi|tr|id|it|pt)\//)) {
+    newPath = currentPath.replace(
+      /^\/(en|fr|es|de|zh|zh-TW|vi|tr|id|it|pt)\//,
+      `/${lang}/`
+    );
+  } else if (currentPath.match(/^\/(en|fr|es|de|zh|zh-TW|vi|tr|id|it|pt)$/)) {
     newPath = `/${lang}`;
   } else {
     newPath = `/${lang}${currentPath}`;
@@ -161,7 +168,7 @@ export const rewriteLinks = (): void => {
       return;
     }
 
-    if (href.match(/^\/(en|fr|de|zh|zh-TW|vi|tr|id|it)\//)) {
+    if (href.match(/^\/(en|fr|es|de|zh|zh-TW|vi|tr|id|it|pt)\//)) {
       return;
     }
     let newHref: string;