fix(wallet-service): 修复 account_sequence 类型从 BIGINT 改为 VARCHAR(20)

与其他服务保持一致，accountSequence 格式为 D + YYMMDD + 5位序号
- wallet_accounts.account_sequence
- wallet_ledger_entries.account_sequence
- deposit_orders.account_sequence
- withdrawal_orders.account_sequence

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/services/wallet-service/prisma/migrations/20241204000000_init/migration.sql

@@ -1,7 +1,7 @@
 -- CreateTable
 CREATE TABLE "wallet_accounts" (
     "wallet_id" BIGSERIAL NOT NULL,
-    "account_sequence" BIGINT NOT NULL,
+    "account_sequence" VARCHAR(20) NOT NULL,
     "user_id" BIGINT NOT NULL,
     "usdt_available" DECIMAL(20,8) NOT NULL DEFAULT 0,
     "usdt_frozen" DECIMAL(20,8) NOT NULL DEFAULT 0,
@@ -33,7 +33,7 @@ CREATE TABLE "wallet_accounts" (
 -- CreateTable
 CREATE TABLE "wallet_ledger_entries" (
     "entry_id" BIGSERIAL NOT NULL,
-    "account_sequence" BIGINT NOT NULL,
+    "account_sequence" VARCHAR(20) NOT NULL,
     "user_id" BIGINT NOT NULL,
     "entry_type" VARCHAR(50) NOT NULL,
     "amount" DECIMAL(20,8) NOT NULL,
@@ -51,7 +51,7 @@ CREATE TABLE "wallet_ledger_entries" (
 -- CreateTable
 CREATE TABLE "deposit_orders" (
     "order_id" BIGSERIAL NOT NULL,
-    "account_sequence" BIGINT NOT NULL,
+    "account_sequence" VARCHAR(20) NOT NULL,
     "user_id" BIGINT NOT NULL,
     "chain_type" VARCHAR(20) NOT NULL,
     "amount" DECIMAL(20,8) NOT NULL,
@@ -82,7 +82,7 @@ CREATE TABLE "settlement_orders" (
 CREATE TABLE "withdrawal_orders" (
     "order_id" BIGSERIAL NOT NULL,
     "order_no" VARCHAR(50) NOT NULL,
-    "account_sequence" BIGINT NOT NULL,
+    "account_sequence" VARCHAR(20) NOT NULL,
     "user_id" BIGINT NOT NULL,
     "amount" DECIMAL(20,8) NOT NULL,
     "fee" DECIMAL(20,8) NOT NULL,