feat(WHE-27): add drizzle db package and typed env config

packages/db/src/schema.ts

@@ -0,0 +1,28 @@
+import { index, integer, pgTable, text, timestamp, uniqueIndex, uuid } from 'drizzle-orm/pg-core'
+
+export const households = pgTable('households', {
+  id: uuid('id').defaultRandom().primaryKey(),
+  name: text('name').notNull(),
+  createdAt: timestamp('created_at', { withTimezone: true }).defaultNow().notNull()
+})
+
+export const members = pgTable(
+  'members',
+  {
+    id: uuid('id').defaultRandom().primaryKey(),
+    householdId: uuid('household_id')
+      .notNull()
+      .references(() => households.id, { onDelete: 'cascade' }),
+    telegramUserId: text('telegram_user_id').notNull(),
+    displayName: text('display_name').notNull(),
+    isAdmin: integer('is_admin').default(0).notNull(),
+    joinedAt: timestamp('joined_at', { withTimezone: true }).defaultNow().notNull()
+  },
+  (table) => ({
+    householdIdx: index('members_household_idx').on(table.householdId),
+    householdTgUserUnique: uniqueIndex('members_household_tg_user_unique').on(
+      table.householdId,
+      table.telegramUserId
+    )
+  })
+)