feat: rebuild frontend with react

frontend/src/services/connections.ts

@@ -0,0 +1,22 @@
+import http from './http'
+import type { BatchCommandResponse, Connection, ConnectionCreateRequest } from '../types'
+
+export function listConnections() {
+  return http.get<Connection[]>('/connections')
+}
+
+export function createConnection(payload: ConnectionCreateRequest) {
+  return http.post<Connection>('/connections', payload)
+}
+
+export function updateConnection(id: number, payload: ConnectionCreateRequest) {
+  return http.put<Connection>(`/connections/${id}`, payload)
+}
+
+export function deleteConnection(id: number) {
+  return http.delete<{ message: string }>(`/connections/${id}`)
+}
+
+export function executeBatchCommand(connectionIds: number[], command: string) {
+  return http.post<BatchCommandResponse>('/connections/batch-command', { connectionIds, command })
+}