feat: 补充注释

server/utils/prisma.ts

@@ -1,3 +1,4 @@
+// server/utils/prisma.ts - Prisma 客户端初始化：使用 MariaDB adapter 并在开发热更新中复用连接池。
 import { PrismaMariaDb } from "@prisma/adapter-mariadb";
 import { PrismaClient } from "~~/app/generated/prisma/client";
 
@@ -16,6 +17,7 @@ type MariaDbPoolConfig = Exclude<
   string
 >;
 
+/** 从 DATABASE_URL 查询参数读取连接池配置，非法值回退到默认值 */
 function getNumberParam(url: URL, name: string, fallback: number) {
   const value = url.searchParams.get(name);
   if (!value) {
@@ -26,6 +28,7 @@ function getNumberParam(url: URL, name: string, fallback: number) {
   return Number.isFinite(parsed) && parsed > 0 ? parsed : fallback;
 }
 
+/** 将 DATABASE_URL 拆成 Prisma MariaDB adapter 需要的连接池配置 */
 function createMariaDbConfig(urlString: string): MariaDbPoolConfig {
   const url = new URL(urlString);
   const database = decodeURIComponent(url.pathname.replace(/^\//, ""));