feat: unified gravity system - VIP members consume gravity instead of unlimited; add monthly gravity top-up cron

backend/scripts/migrate-gravity.ts

@@ -0,0 +1,54 @@
+/**
+ * 引力值迁移脚本
+ * 将现有用户的多维额度合并到 gravity 字段
+ * 公式: gravity = interviewCredits×5 + resumeOptimizeCredits×3 + resumeDownloadCredits×2 + shareCredits×1 + remaining×5
+ * 用法: npx ts-node --project tsconfig.json scripts/migrate-gravity.ts
+ */
+import { NestFactory } from '@nestjs/core'
+import { AppModule } from '../src/app.module'
+import { getModelToken } from '@nestjs/mongoose'
+import { User, UserDocument } from '../src/modules/user/user.schema'
+import { Model } from 'mongoose'
+
+async function bootstrap() {
+  const app = await NestFactory.createApplicationContext(AppModule)
+  const userModel = app.get<Model<UserDocument>>(getModelToken(User.name))
+
+  const total = await userModel.countDocuments().exec()
+  console.log(`Total users: ${total}`)
+
+  let migrated = 0
+  let skipped = 0
+  const cursor = userModel.find().cursor()
+
+  for await (const user of cursor) {
+    const interviewVal = (user.interviewCredits ?? 0) * 5
+    const optimizeVal = (user.resumeOptimizeCredits ?? 0) * 3
+    const downloadVal = (user.resumeDownloadCredits ?? 0) * 2
+    const oldRemainVal = (user.remaining ?? 0) * 5
+    const shareVal = (user.shareCredits ?? 0) * 1
+    const totalGravity = interviewVal + optimizeVal + downloadVal + oldRemainVal + shareVal
+
+    if (totalGravity <= 0 && (user.gravity ?? 0) === 0) {
+      skipped++
+      continue
+    }
+
+    await userModel.findByIdAndUpdate(user._id, {
+      $set: {
+        gravity: Math.max(user.gravity ?? 0, totalGravity),
+        interviewCredits: 0,
+        resumeOptimizeCredits: 0,
+        resumeDownloadCredits: 0,
+        remaining: 0,
+        shareCredits: 0,
+      },
+    }).exec()
+    migrated++
+  }
+
+  console.log(`Migrated: ${migrated}, Skipped (no credits): ${skipped}`)
+  await app.close()
+}
+
+bootstrap().catch(console.error)