feat: Add type and usageData columns to the item schema to support item usage effects.

src/db/schema.ts

@@ -50,6 +50,9 @@ export const items = pgTable('items', {
     rarity: varchar('rarity', { length: 20 }).default('Common'),
 
     // Economy & Visuals
+    type: varchar('type', { length: 50 }).notNull().default('MATERIAL'),
+    // Examples: 'CONSUMABLE', 'EQUIPMENT', 'MATERIAL'
+    usageData: jsonb('usage_data').default({}),
     price: bigint('price', { mode: 'bigint' }),
     iconUrl: text('icon_url').notNull(),
     imageUrl: text('image_url').notNull(),