fix: simplify balance billing and govern operation logs

api/prisma/schema.prisma

@@ -154,6 +154,29 @@ model OperationLog {
 
   @@index([tenantId, createdAt])
   @@index([userId, createdAt])
+  @@index([createdAt])
+  @@index([resource, createdAt])
+}
+
+model OperationLogArchive {
+  originalId String   @id
+  tenantId   String?
+  userId     String?
+  action     String
+  resource   String
+  resourceId String?
+  ipAddress  String?
+  userAgent  String?
+  detail     Json?
+  createdAt  DateTime
+  archiveMonth String
+  archivedAt DateTime @default(now())
+
+  @@index([tenantId, createdAt])
+  @@index([userId, createdAt])
+  @@index([createdAt])
+  @@index([resource, createdAt])
+  @@index([archiveMonth])
 }
 
 model FileObject {
@@ -240,26 +263,10 @@ model DrainageField {
   channelReportFields ChannelReportField[]
 }
 
-model BillingPlan {
-  id          String   @id @default(cuid())
-  name        String
-  priceCents  Int
-  smsUnits    Int
-  validDays   Int
-  status      String   @default("active")
-  description String?
-  createdAt   DateTime @default(now())
-  updatedAt   DateTime @updatedAt
-
-  rechargeOrders RechargeOrder[]
-}
-
 model TenantAccount {
   id           String   @id @default(cuid())
   tenantId     String
   balanceCents Int      @default(0)
-  smsUnits     Int      @default(0)
-  creditCents  Int      @default(0)
   status       String   @default("active")
   createdAt    DateTime @default(now())
   updatedAt    DateTime @updatedAt
@@ -274,7 +281,6 @@ model AccountTransaction {
   tenantId        String
   transactionType String
   amountCents     Int      @default(0)
-  smsUnits        Int      @default(0)
   balanceAfter    Int      @default(0)
   relatedType     String?
   relatedId       String?
@@ -301,10 +307,8 @@ model BillingRule {
 model RechargeOrder {
   id          String   @id @default(cuid())
   tenantId    String
-  planId      String?
   orderNo     String   @unique
   amountCents Int
-  smsUnits    Int      @default(0)
   status      String   @default("created")
   payMethod   String?
   paidAt      DateTime?
@@ -313,8 +317,7 @@ model RechargeOrder {
   createdAt   DateTime @default(now())
   updatedAt   DateTime @updatedAt
 
-  tenant Tenant       @relation(fields: [tenantId], references: [id])
-  plan   BillingPlan? @relation(fields: [planId], references: [id])
+  tenant Tenant @relation(fields: [tenantId], references: [id])
 
   @@index([tenantId, createdAt])
 }