feat: 添加Docker配置，集成my_oss图片服务

lib/db.ts

@@ -1,11 +1,11 @@
 import mysql from 'mysql2/promise';
 
 const pool = mysql.createPool({
-  host: '192.168.0.196',
-  port: 3306,
-  user: 'smalltown',
-  password: 'MyPassword1+',
-  database: 'smalltown',
+  host: process.env.DB_HOST || '192.168.0.196',
+  port: parseInt(process.env.DB_PORT || '3306'),
+  user: process.env.DB_USER || 'smalltown',
+  password: process.env.DB_PASSWORD || 'MyPassword1+',
+  database: process.env.DB_NAME || 'smalltown',
   waitForConnections: true,
   connectionLimit: 10,
   queueLimit: 0