refactor(api): improve http client implementation

- Removed redundant comments and code annotations
- Simplified type definitions and interface declarations
- Streamlined URL construction logic
- Enhanced body handling for FormData and JSON payloads
- Optimized header normalization process
- Cleaned up API method signatures
- Improved content-type handling for form data
- Removed unnecessary blank lines and formatting clutter

src/lib/api/httpClient.ts

@@ -1,11 +1,8 @@
-// src/lib/api/httpClient.ts
 
-import { browser } from '$app/environment'; // SvelteKit 环境变量
+import { browser } from '$app/environment';
 import { log } from '$lib/log.ts';
 
-// 1. 完善类型定义，确保 FormData 被允许
-// 假设 JsonValue 和 JsonObject 在你的 types/http.ts 中定义
-// 这里为了示例完整性，我做了一个简单的宽泛定义，你可以替换回你的 import
+
 type JsonValue = string | number | boolean | null | JsonObject | JsonValue[];
 interface JsonObject { [key: string]: JsonValue }
 type HttpMethod = 'GET' | 'POST' | 'PUT' | 'DELETE' | 'PATCH' | 'HEAD';
@@ -16,15 +13,13 @@ export interface ApiResult<T> {
 	data: T;
 }
 
-// 扩展 RequestOptions 以支持 SvelteKit 的 custom fetch
 interface RequestOptions extends Omit<RequestInit, 'method' | 'body'> {
 	body?: JsonObject | FormData | object;
-	customFetch?: typeof fetch; // 允许传入 SvelteKit 的 load fetch
+	customFetch?: typeof fetch;
 }
 
 const API_BASE_URL = import.meta.env.VITE_PUBLIC_API_URL || 'http://localhost:18888/api';
 
-// 辅助函数：规范化 Headers
 const normalizeHeaders = (headers?: HeadersInit): Record<string, string> => {
 	const result: Record<string, string> = {};
 	if (!headers) return result;
@@ -65,10 +60,8 @@ const httpRequest = async <T>(
 	method: HttpMethod,
 	options: RequestOptions = {}
 ): Promise<ApiResult<T>> => {
-	// 拼接 URL
 	const fullUrl = url.startsWith('http') ? url : `${API_BASE_URL}${url}`;
 
-	// 2. 提取 customFetch，优先使用传入的 fetch (解决 SSR Cookie 问题)
 	const { body, headers, customFetch, ...rest } = options;
 	const fetchImpl = customFetch || fetch;
 
@@ -77,14 +70,11 @@ const httpRequest = async <T>(
 
 	const canHaveBody = method !== 'GET' && method !== 'HEAD';
 
-	// 3. 处理 Body 和 Content-Type 的核心逻辑
 	if (canHaveBody) {
 		if (body instanceof FormData) {
 			requestBody = body;
-			// 【关键修复】如果是 FormData，必须删除 Content-Type，让浏览器自动设置 boundary
 			delete requestHeaders['content-type'];
 		} else if (body) {
-			// 如果是普通对象，强制设置为 JSON
 			requestHeaders['content-type'] = 'application/json';
 			requestBody = JSON.stringify(body);
 		}
@@ -134,7 +124,6 @@ const httpRequest = async <T>(
 	}
 };
 
-// 4. 更新 API 方法签名，允许 body 为 FormData
 export const api = {
 	get: <T>(url: string, options?: RequestOptions) =>
 		httpRequest<T>(url, 'GET', options),