Fix SSL SAN cert + React hydration #423

- SAN cert covers all 5 PWA domains (tasks,cal,plans,goals,chat)
- i18n hydration: SSR uses cs default, localStorage after mount
- Matches ThemeProvider pattern

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/tasks/app/login/page.tsx

@@ -56,7 +56,7 @@ export default function LoginPage() {
                 value={email}
                 onChange={(e) => setEmail(e.target.value)}
                 className="w-full px-3 py-2.5 border border-gray-300 dark:border-gray-600 rounded-lg bg-white dark:bg-gray-800 focus:ring-2 focus:ring-blue-500 focus:border-transparent outline-none"
-                placeholder="vas@email.cz"
+                placeholder={t("auth.emailPlaceholder")}
                 autoFocus
                 autoComplete="email"
               />