feat: rebrand to ConvertX-CN, fix TypeScript error, add docs

- Fix TypeScript TS2345 error in i18n/service.ts by parsing cookie from header
- Rebrand all ConvertX references to ConvertX-CN
- Change default language from en to zh-TW
- Fix footer to always display English 'Powered by ConvertX-CN'
- Update GitHub links to pi-docket/ConvertX-CN
- Add /docs folder with documentation:
  - getting-started.md
  - configuration.md
  - converters.md
  - i18n.md
- Update all locale files with new branding

src/components/base.tsx

@@ -3,7 +3,7 @@ import { type SupportedLocale, defaultLocale, getTranslations } from "../i18n";
 
 export const BaseHtml = ({
   children,
-  title = "ConvertX",
+  title = "ConvertX-CN",
   webroot = "",
   locale = defaultLocale,
 }: {
@@ -33,17 +33,17 @@ export const BaseHtml = ({
       {children}
       <footer class="w-full">
         <div class="p-4 text-center text-sm text-neutral-500">
-          <span>{locale === "en" ? "Powered by " : `${getTranslations(locale).common.poweredBy} `}</span>
+          <span>Powered by </span>
           <a
-            href="https://github.com/C4illin/ConvertX"
+            href="https://github.com/pi-docket/ConvertX-CN"
             class={`
               text-neutral-400
               hover:text-accent-500
             `}
           >
-            ConvertX{" "}
+            ConvertX-CN
           </a>
-          <span safe>v{version || ""}</span>
+          <span safe> v{version || ""}</span>
         </div>
       </footer>
     </body>

src/components/header.tsx

@@ -106,7 +106,7 @@ export const Header = ({
         <ul>
           <li>
             <strong>
-              <a href={`${webroot}/`}>ConvertX</a>
+              <a href={`${webroot}/`}>ConvertX-CN</a>
             </strong>
           </li>
         </ul>