docs: 添加代理设置说明并优化API请求代码结构

在README中为无法直接访问Google服务的用户添加代理设置说明
优化gemini-core.js中的API请求代码结构以提高可读性

README-EN.md

@@ -129,6 +129,23 @@ This project consists of three core files, each with its own specific function:
     ```
 
 #### 💻 Call the API (Default API Key: `123456`)
+> **Hint**: If you are in an environment where you cannot directly access Google services, please set up a global HTTP/HTTPS proxy for your terminal first.
+> 
+> - **Windows (CMD):**
+>   ```cmd
+>   set http_proxy=http://127.0.0.1:7890
+>   set https_proxy=http://127.0.0.1:7890
+>   ```
+> - **Windows (PowerShell):**
+>   ```powershell
+>   $env:http_proxy="http://127.0.0.1:7890"
+>   $env:https_proxy="http://127.0.0.1:7890"
+>   ```
+> - **macOS/Linux (Bash/Zsh):**
+>   ```bash
+>   export http_proxy=http://127.0.0.1:7890
+>   export https_proxy=http://127.0.0.1:7890
+>   ```
 *   **List Models**
     ```bash
     curl "http://localhost:3000/v1beta/models?key=123456"
@@ -161,6 +178,7 @@ This project consists of three core files, each with its own specific function:
     ```
 
 #### 💻 Call the API (as an OpenAI client)
+
 *   **List Models**
     ```bash
     curl http://localhost:8000/v1/models \

README.md

@@ -123,12 +123,29 @@
     ```bash
     node gemini-api-server.js --oauth-creds-file "/path/to/your/oauth_creds.json"
     ```
-*   **通过指定项目ID启动** (例如，用于多项目环境)
+*   **通过指定项目ID启动** (例如，用于多项目环境或必须指定项目ID的用户)
     ```bash
     node gemini-api-server.js --project-id your-gcp-project-id
     ```
 
 #### 💻 调用 API (默认 API Key: `123456`)
+> **提示**: 如果您在无法直接访问 Google 服务的环境中使用，请先为您的终端设置全局 HTTP/HTTPS 代理。
+> 
+> - **Windows (CMD):**
+>   ```cmd
+>   set http_proxy=http://127.0.0.1:7890
+>   set https_proxy=http://127.0.0.1:7890
+>   ```
+> - **Windows (PowerShell):**
+>   ```powershell
+>   $env:http_proxy="http://127.0.0.1:7890"
+>   $env:https_proxy="http://127.0.0.1:7890"
+>   ```
+> - **macOS/Linux (Bash/Zsh):**
+>   ```bash
+>   export http_proxy=http://127.0.0.1:7890
+>   export https_proxy=http://127.0.0.1:7890
+>   ```
 *   **列出模型**
     ```bash
     curl "http://localhost:3000/v1beta/models?key=123456"
@@ -161,6 +178,7 @@
     ```
 
 #### 💻 调用 API (以 OpenAI 客户端方式)
+
 *   **列出模型**
     ```bash
     curl http://localhost:8000/v1/models \

gemini-core.js

@@ -294,11 +294,14 @@ export class GeminiApiService {
 
     async callApi(method, body, isRetry = false) {
         try {
-            const res = await this.authClient.request({
+            const requestOptions = {
                 url: `${CODE_ASSIST_ENDPOINT}/${CODE_ASSIST_API_VERSION}:${method}`,
-                method: "POST", headers: { "Content-Type": "application/json" },
+                method: "POST",
-                responseType: "json", body: JSON.stringify(body),
+                headers: { "Content-Type": "application/json" },
-            });
+                responseType: "json",
+                body: JSON.stringify(body),
+            };
+            const res = await this.authClient.request(requestOptions);
             return res.data;
         } catch (error) {
             if (error.response?.status === 401 && !isRetry) {
@@ -312,11 +315,15 @@ export class GeminiApiService {
 
     async * streamApi(method, body, isRetry = false) {
         try {
-            const res = await this.authClient.request({
+            const requestOptions = {
                 url: `${CODE_ASSIST_ENDPOINT}/${CODE_ASSIST_API_VERSION}:${method}`,
-                method: "POST", params: { alt: "sse" }, headers: { "Content-Type": "application/json" },
+                method: "POST",
-                responseType: "stream", body: JSON.stringify(body),
+                params: { alt: "sse" },
-            });
+                headers: { "Content-Type": "application/json" },
+                responseType: "stream",
+                body: JSON.stringify(body),
+            };
+            const res = await this.authClient.request(requestOptions);
             if (res.status !== 200) {
                 let errorBody = '';
                 for await (const chunk of res.data) errorBody += chunk.toString();