优化页面交互并增强 Provider 配置能力

- 表单下拉框不再用 label 包裹，改为 div + aria-label，避免点击后
  下拉面板瞬间关闭
- Provider 卡片新增「从上游获取模型」和「修改」入口，支持编辑
  base URL、API Key 与 api_mode，凭据写入对应的环境变量
- 服务端抽出 provider-model-discovery 统一不同 api_mode 的模型发现，
  旧的 custom_providers 与新的 providers 字典结构都能正确更新
- Agent Bridge 改为后台启动，HTTP 接口在 Python 运行时就绪前即可用；
  worker 连接被拒时按类型重试，不重放可能已产生副作用的请求
- 断线重连后恢复 profiles、models 与会话列表，健康检查改为自调度
  的 setTimeout，离线时 2 秒后重试
- 批量删除确认文案改用 Popconfirm content，避免变成侧栏触发器文本

packages/server/src/services/hermes/agent-bridge/client.ts

@@ -373,10 +373,23 @@ export class AgentBridgeClient {
         }, '[agent-bridge-client] request')
       }
       try {
-        const socket = await this.connectSocket()
-        socket.write(`${JSON.stringify(payload)}\n`)
-        const raw = await this.readResponse(socket, timeoutMs)
-        const response = JSON.parse(raw) as { ok?: boolean; error?: string }
+        const workerConnectDeadline = Date.now() + Math.max(0, this.connectRetryMs)
+        let response: { ok?: boolean; error?: string; error_type?: string }
+        for (;;) {
+          const socket = await this.connectSocket()
+          socket.write(`${JSON.stringify(payload)}\n`)
+          const raw = await this.readResponse(socket, timeoutMs)
+          response = JSON.parse(raw) as typeof response
+          // The broker reports worker connect failures before any request bytes
+          // reach the worker. Only these typed failures are safe to replay;
+          // timeouts, lost responses and agent errors may have side effects.
+          const workerNotListening = response.ok === false && (
+            (response.error_type === 'ConnectionRefusedError' && /^\[Errno (111|61|10061)\]/.test(response.error || '')) ||
+            (response.error_type === 'FileNotFoundError' && /^\[Errno 2\]/.test(response.error || ''))
+          )
+          if (!workerNotListening || Date.now() >= workerConnectDeadline) break
+          await delay(100)
+        }
         if (!response.ok) {
           const error = new AgentBridgeError(response.error || 'Agent bridge request failed')
           error.response = response