feat: use Nitro KV Storage to get stats from Redis

[rwd]

Configure Redis for ds4ch app with:

NUXT_REDIS_URL=redis://localhost:16379

(where the Redis db is one populated by the portal.js app's cachers)

Then, with the ds4ch app running, http://localhost:3000/api/stats/items/typeCounts will return the item type counts.

From a Nuxt page or component, retrieve this with:

const { data } = await useFetch('/api/stats/items/typeCounts')

Documentation:

• Nuxt server directory
• Nuxt server storage (via Nitro)
• unstorage Redis driver

[github-actions]

JIRA ticket: EC-7276