feat: 完善 Gemini 功能与 Claude 保持一致

- 添加 Gemini 账户的 schedulable 字段和调度开关 API
- 实现 Gemini 调度器的模型过滤功能
- 完善 Gemini 数据统计，记录 token 使用量
- 修复 Gemini 流式响应的 SSE 解析和 AbortController 支持
- 在教程页面和 README 中添加 Gemini CLI 环境变量说明
- 修复前端 Gemini 账户调度开关限制

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

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

src/services/unifiedClaudeScheduler.js

@@ -18,7 +18,7 @@ class UnifiedClaudeScheduler {
         if (apiKeyData.claudeAccountId.startsWith('group:')) {
           const groupId = apiKeyData.claudeAccountId.replace('group:', '');
           logger.info(`🎯 API key ${apiKeyData.name} is bound to group ${groupId}, selecting from group`);
-          return await this.selectAccountFromGroup(groupId, sessionHash, requestedModel, apiKeyData);
+          return await this.selectAccountFromGroup(groupId, sessionHash, requestedModel);
         }
         
         // 普通专属账户
@@ -370,7 +370,7 @@ class UnifiedClaudeScheduler {
   }
 
   // 👥 从分组中选择账户
-  async selectAccountFromGroup(groupId, sessionHash = null, requestedModel = null, apiKeyData = null) {
+  async selectAccountFromGroup(groupId, sessionHash = null, requestedModel = null) {
     try {
       // 获取分组信息
       const group = await accountGroupService.getGroup(groupId);
@@ -426,7 +426,7 @@ class UnifiedClaudeScheduler {
           }
         } else if (group.platform === 'gemini') {
           // Gemini暂时不支持，预留接口
-          logger.warn(`⚠️ Gemini group scheduling not yet implemented`);
+          logger.warn('⚠️ Gemini group scheduling not yet implemented');
           continue;
         }