feat(web): add login and register pages with auth store

- API client with token refresh interceptor
- Auth API functions (login, register, logout, getMe)
- Auth store with Zustand persistence
- Auth layout with centered card design
- Login page with form validation
- Register page with company and user data
- Environment example file

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

apps/web/app/(auth)/login/page.tsx

@@ -0,0 +1,90 @@
+'use client';
+
+import { useState } from 'react';
+import { useRouter } from 'next/navigation';
+import Link from 'next/link';
+import { Button } from '@/components/ui/button';
+import { Input } from '@/components/ui/input';
+import { Label } from '@/components/ui/label';
+import { Card, CardContent, CardDescription, CardFooter, CardHeader, CardTitle } from '@/components/ui/card';
+import { login } from '@/lib/api/auth';
+import { useAuthStore } from '@/stores/auth-store';
+
+export default function LoginPage() {
+  const router = useRouter();
+  const { setUser, setTokens } = useAuthStore();
+  const [isLoading, setIsLoading] = useState(false);
+  const [error, setError] = useState('');
+
+  async function handleSubmit(e: React.FormEvent<HTMLFormElement>) {
+    e.preventDefault();
+    setIsLoading(true);
+    setError('');
+
+    const formData = new FormData(e.currentTarget);
+    const email = formData.get('email') as string;
+    const password = formData.get('password') as string;
+
+    try {
+      const response = await login({ email, password });
+      setTokens(response.accessToken, response.refreshToken);
+      setUser(response.user);
+      router.push('/dashboard');
+    } catch (err: any) {
+      setError(err.response?.data?.message || 'Error al iniciar sesión');
+    } finally {
+      setIsLoading(false);
+    }
+  }
+
+  return (
+    <Card>
+      <CardHeader className="text-center">
+        <CardTitle className="text-2xl">Iniciar Sesión</CardTitle>
+        <CardDescription>
+          Ingresa tus credenciales para acceder a tu cuenta
+        </CardDescription>
+      </CardHeader>
+      <form onSubmit={handleSubmit}>
+        <CardContent className="space-y-4">
+          {error && (
+            <div className="p-3 text-sm text-destructive bg-destructive/10 rounded-md">
+              {error}
+            </div>
+          )}
+          <div className="space-y-2">
+            <Label htmlFor="email">Email</Label>
+            <Input
+              id="email"
+              name="email"
+              type="email"
+              placeholder="tu@email.com"
+              required
+            />
+          </div>
+          <div className="space-y-2">
+            <Label htmlFor="password">Contraseña</Label>
+            <Input
+              id="password"
+              name="password"
+              type="password"
+              placeholder="••••••••"
+              required
+            />
+          </div>
+        </CardContent>
+        <CardFooter className="flex flex-col gap-4">
+          <Button type="submit" className="w-full" disabled={isLoading}>
+            {isLoading ? 'Iniciando sesión...' : 'Iniciar Sesión'}
+          </Button>
+          <p className="text-sm text-muted-foreground text-center">
+            ¿No tienes cuenta?{' '}
+            <Link href="/register" className="text-primary hover:underline">
+              Regístrate
+            </Link>
+          </p>
+        </CardFooter>
+      </form>
+    </Card>
+  );
+}