fix(stats): make unique users migration idempotent

packages/stats/core/src/ensure-unique-users.ts

@@ -0,0 +1,26 @@
+import { Client } from "@planetscale/database"
+import { Resource } from "sst/resource"
+
+const tables = ["geo_stat", "model_stat", "provider_stat"] as const
+
+const client = new Client({ url: Resource.StatsDatabase.url })
+
+await tables.reduce(
+  (promise, table) => promise.then(() => ensureUniqueUsersColumn(table)),
+  Promise.resolve(),
+)
+
+async function ensureUniqueUsersColumn(table: (typeof tables)[number]) {
+  const result = await client.execute<{ column_name: string }>(
+    "SELECT column_name FROM information_schema.columns WHERE table_schema = database() AND table_name = ? AND column_name = 'unique_users'",
+    [table],
+  )
+
+  if (result.rows.length > 0) {
+    console.log(`unique_users column already exists on ${table}`)
+    return
+  }
+
+  await client.execute(`ALTER TABLE \`${table}\` ADD \`unique_users\` bigint NOT NULL DEFAULT 0`)
+  console.log(`added unique_users column to ${table}`)
+}