feat: Add shopping cart to catalog page with sidebar

src/components/catalog/Card.vue

@@ -0,0 +1,107 @@
+<template>
+  <v-card>
+    <v-row no-gutters align="center" class="w-100">
+      <v-col cols="12" md="3" class="d-flex">
+        <v-img :src="product.img" class="product-img" contain></v-img>
+      </v-col>
+
+      <v-col cols="12" md="6">
+        <v-card-title>{{ product.name }}</v-card-title>
+        <v-card-subtitle>{{ product.description }}</v-card-subtitle>
+        <div class="prices mt-2">
+          <div class="price-line">
+            Precio unitario: <strong>{{ currency(product.price) }}</strong>
+          </div>
+          <div class="price-line">
+            Precio total:
+            <strong>{{ currency(product.price * product.quantity) }}</strong>
+          </div>
+        </div>
+      </v-col>
+
+      <v-col cols="12" md="3" class="d-flex align-center justify-end">
+        <div class="quantity-controls">
+          <v-btn small text class="qty-btn" @click="decrease(product)"
+            ><v-icon small>mdi-minus</v-icon></v-btn
+          >
+          <v-text-field
+            v-model.number="product.quantity"
+            type="number"
+            min="0"
+            class="quantity-input"
+            dense
+            outlined
+            hide-details
+            aria-label="Cantidad"
+          />
+          <v-btn small text class="qty-btn" @click="handleIncrease"
+            ><v-icon small>mdi-plus</v-icon></v-btn>
+        </div>
+      </v-col>
+    </v-row>
+  </v-card>
+</template>
+
+<script>
+export default {
+  props: {
+    product: {
+      type: Object,
+      required: true
+    },
+    increase: {
+      type: Function,
+      required: true
+    },
+    decrease: {
+      type: Function,
+      required: true
+    },
+    currency: {
+      type: Function,
+      required: true
+    }
+  },
+  methods: {
+    handleIncrease() {
+      this.increase(this.product);
+      this.$emit('add-to-cart', this.product);
+    }
+  }
+}
+</script>
+
+<style scoped>
+.product-img {
+  width: 150px;
+  height: 100px;
+  border-radius: 6px;
+  object-fit: cover;
+}
+.quantity-controls {
+  display: inline-flex;
+  align-items: center;
+  justify-content: flex-end;
+  gap: 8px;
+}
+.prices .price-line {
+  margin-bottom: 4px;
+}
+.quantity-input {
+  max-width: 90px;
+}
+.quantity-input input {
+  text-align: center;
+}
+.qty-btn {
+  min-width: 36px !important;
+  height: 36px !important;
+  border-radius: 18px !important;
+}
+@media (max-width: 600px) {
+  .product-img {
+    width: 120px;
+    height: 80px;
+  }
+}
+</style>

src/components/catalog/Cart.vue

@@ -0,0 +1,83 @@
+<template>
+  <v-card>
+    <v-card-title class="d-flex align-center">
+      <v-icon class="mr-2">mdi-cart</v-icon>
+      Carrito
+      <v-chip v-if="cartCount" color="primary" class="ml-2">{{ cartCount }}</v-chip>
+    </v-card-title>
+    
+    <v-divider></v-divider>
+    
+    <v-card-text v-if="cartItems.length === 0" class="text-center grey--text">
+      El carrito está vacío
+    </v-card-text>
+    
+    <v-list v-else density="compact" max-height="300" class="overflow-y-auto">
+      <v-list-item v-for="item in cartItems" :key="item.id">
+        <template v-slot:prepend>
+          <v-avatar size="40" rounded>
+            <v-img :src="item.img" cover></v-img>
+          </v-avatar>
+        </template>
+        
+        <v-list-item-title>{{ item.name }}</v-list-item-title>
+        <v-list-item-subtitle>
+          {{ item.quantity }} x {{ currency(item.price) }}
+        </v-list-item-subtitle>
+        
+        <template v-slot:append>
+          <div class="d-flex align-center">
+            <strong>{{ currency(item.price * item.quantity) }}</strong>
+            <v-btn 
+              icon="mdi-delete" 
+              size="small" 
+              variant="text" 
+              color="red"
+              class="ml-2"
+              @click="$emit('remove', item.id)"
+            ></v-btn>
+          </div>
+        </template>
+      </v-list-item>
+    </v-list>
+    
+    <v-divider v-if="cartItems.length > 0"></v-divider>
+    
+    <v-card-text v-if="cartItems.length > 0">
+      <div class="d-flex justify-space-between align-center">
+        <strong>Total:</strong>
+        <strong class="text-h6">{{ currency(cartTotal) }}</strong>
+      </div>
+    </v-card-text>
+    
+    <v-card-actions v-if="cartItems.length > 0">
+      <v-btn color="primary" block @click="$emit('checkout')">
+        Finalizar Compra
+      </v-btn>
+    </v-card-actions>
+  </v-card>
+</template>
+
+<script>
+export default {
+  name: 'Cart',
+  props: {
+    cartItems: {
+      type: Array,
+      default: () => []
+    },
+    currency: {
+      type: Function,
+      required: true
+    }
+  },
+  computed: {
+    cartCount() {
+      return this.cartItems.reduce((sum, item) => sum + item.quantity, 0);
+    },
+    cartTotal() {
+      return this.cartItems.reduce((sum, item) => sum + (item.price * item.quantity), 0);
+    }
+  }
+}
+</script>