chore: update default account and add example data

- Update default login email to xinmi@local.com
- Update default password to 12345678 (and bcrypt hash in crm.sql)
- Add example customers, products, and contracts to init SQL
- Fix Docker env interpolation for VITE_API_BASE_URL
- Hardcode local backend API URL in frontend .env files
- Update README and docs to reflect new default credentials

web/src/views/Login.vue

@@ -44,7 +44,7 @@ import { initDatabase } from '../api/common';
 
 // 初始化数据库（只会在生产环境中初始化）
 onMounted(() => {
-    if (formData.email == '1655064994@qq.com') {
+    if (formData.email == 'xinmi@local.com') {
         message.loading('正在初始化数据...', 2.5).then(() => {
             initDatabase().then((res) => {
                 if (res.data.code == 0) {
@@ -61,8 +61,8 @@ onMounted(() => {
 const router = useRouter()
 
 const formData = reactive({
-    email: '1655064994@qq.com',
-    password: '1655064994',
+    email: 'xinmi@local.com',
+    password: '12345678',
     remember: true,
 })