feat: 为API Key添加模型限制功能

- 前端：在API Key创建和编辑表单中添加模型限制开关和标签输入
- 前端：支持动态添加/删除限制的模型列表
- 后端：更新API Key数据结构，新增enableModelRestriction和restrictedModels字段
- 后端：在中转请求时检查模型访问权限
- 修复：Enter键提交表单问题，使用@keydown.enter.prevent
- 优化：限制模型数据持久化，关闭开关时不清空数据

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/services/claudeRelayService.js

@@ -22,6 +22,24 @@ class ClaudeRelayService {
     let upstreamRequest = null;
     
     try {
+      // 检查模型限制
+      if (apiKeyData.enableModelRestriction && apiKeyData.restrictedModels && apiKeyData.restrictedModels.length > 0) {
+        const requestedModel = requestBody.model;
+        if (requestedModel && apiKeyData.restrictedModels.includes(requestedModel)) {
+          logger.warn(`🚫 Model restriction violation for key ${apiKeyData.name}: Attempted to use restricted model ${requestedModel}`);
+          return {
+            statusCode: 403,
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify({
+              error: {
+                type: 'forbidden',
+                message: '暂无该模型访问权限'
+              }
+            })
+          };
+        }
+      }
+      
       // 生成会话哈希用于sticky会话
       const sessionHash = sessionHelper.generateSessionHash(requestBody);
       
@@ -419,6 +437,26 @@ class ClaudeRelayService {
   // 🌊 处理流式响应（带usage数据捕获）
   async relayStreamRequestWithUsageCapture(requestBody, apiKeyData, responseStream, clientHeaders, usageCallback) {
     try {
+      // 检查模型限制
+      if (apiKeyData.enableModelRestriction && apiKeyData.restrictedModels && apiKeyData.restrictedModels.length > 0) {
+        const requestedModel = requestBody.model;
+        if (requestedModel && apiKeyData.restrictedModels.includes(requestedModel)) {
+          logger.warn(`🚫 Model restriction violation for key ${apiKeyData.name}: Attempted to use restricted model ${requestedModel}`);
+          
+          // 对于流式响应，需要写入错误并结束流
+          const errorResponse = JSON.stringify({
+            error: {
+              type: 'forbidden',
+              message: '暂无该模型访问权限'
+            }
+          });
+          
+          responseStream.writeHead(403, { 'Content-Type': 'application/json' });
+          responseStream.end(errorResponse);
+          return;
+        }
+      }
+      
       // 生成会话哈希用于sticky会话
       const sessionHash = sessionHelper.generateSessionHash(requestBody);