feat: boton de mostrar/ocultar clave en todos los campos de contraseña

Componente reutilizable PasswordInput (icono de ojo) usado en login, registro,
restablecer clave, cambiar clave, crear usuario y la clave SMTP de
Configuracion, para que el usuario pueda verificar que la esta escribiendo
correctamente.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

frontend/src/pages/Login/LoginPage.jsx

@@ -5,6 +5,7 @@ import { useAuth } from '../../context/auth-context.jsx';
 import { useUi } from '../../context/ui-context.jsx';
 import { Field } from '../../components/Field.jsx';
 import { Button } from '../../components/Button.jsx';
+import { PasswordInput } from '../../components/PasswordInput.jsx';
 import logoDark from '../../assets/logoLinkedCorpTxt.png';
 import logoLight from '../../assets/logoLinkedCorpTxtBlack.png';
 
@@ -43,7 +44,7 @@ export default function LoginPage() {
           <input className="input" type="email" value={email} onChange={(e) => setEmail(e.target.value)} required autoFocus />
         </Field>
         <Field label={t('login_password')}>
-          <input className="input" type="password" value={password} onChange={(e) => setPassword(e.target.value)} required />
+          <PasswordInput value={password} onChange={(e) => setPassword(e.target.value)} required />
         </Field>
         <Button variant="accent" icon={LogIn} type="submit" disabled={loading} style={{ width: '100%', justifyContent: 'center' }}>
           {t('login_submit')}