fix(security): Q2 Chunk 1 — 密钥外部化与启动强制检查

- default.toml 敏感值改为占位符，强制通过环境变量注入
- 启动时拒绝默认 JWT 密钥和数据库 URL
- 移除 super_admin_password 硬编码 fallback
- 移除 From<AppError> for AuthError 反向映射，5 处调用点改为显式 map_err
- .gitignore 添加 .test_token 和测试产物

crates/erp-auth/src/service/user_service.rs

@@ -200,7 +200,8 @@ impl UserService {
             .filter(|u| u.tenant_id == tenant_id && u.deleted_at.is_none())
             .ok_or_else(|| AuthError::Validation("用户不存在".to_string()))?;
 
-        let next_ver = check_version(req.version, user_model.version)?;
+        let next_ver = check_version(req.version, user_model.version)
+            .map_err(|e| AuthError::Validation(e.to_string()))?;
 
         let mut active: user::ActiveModel = user_model.into();