fix: correct BackToNavigation href paths and remove client directive

- Add leading slashes to href paths in model-providers and vendors pages
- Remove unnecessary 'use client' directive from BackToNavigation component
- Update JSDoc example to show correct href format with leading slash

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: ericyangpan

src/app/[locale]/model-providers/[slug]/page.tsx

@@ -176,7 +176,7 @@ export default async function ProviderPage({
       />
 
       {/* Navigation */}
-      <BackToNavigation href="model-providers" title={t('allModelProviders')} />
+      <BackToNavigation href="/model-providers" title={t('allModelProviders')} />
 
       <Footer />
     </>

src/app/[locale]/vendors/[slug]/page.tsx

@@ -173,7 +173,7 @@ export default async function VendorPage({
       <VendorModels models={vendorModels} locale={locale} title={t('models')} />
 
       {/* Navigation */}
-      <BackToNavigation href="vendors" title={t('allVendors')} />
+      <BackToNavigation href="/vendors" title={t('allVendors')} />
 
       <Footer />
     </>

src/components/controls/BackToNavigation.tsx

@@ -1,5 +1,3 @@
-'use client'
-
 import { useTranslations } from 'next-intl'
 import { Link } from '@/i18n/navigation'
 
@@ -23,7 +21,7 @@ interface BackToNavigationProps {
  * Automatically handles internationalization for common text like "Back to" and "[INDEX]".
  *
  * @example
- * <BackToNavigation href="ides" title="All IDEs" />
+ * <BackToNavigation href="/ides" title="All IDEs" />
  */
 export function BackToNavigation({ href, title }: BackToNavigationProps) {
   const t = useTranslations('components.backToNavigation')