feat: 添加获取TLS证书内容的API和前端支持，更新相关组件

atsf_server/web/features/tls-certificates/api/tls-certificates.ts

@@ -1,6 +1,7 @@
 import { apiRequest } from '@/lib/api/client';
 
 import type {
+  TlsCertificateContentItem,
   TlsCertificateDetailItem,
   TlsCertificateFileImportPayload,
   TlsCertificateItem,
@@ -22,6 +23,10 @@ export function getTlsCertificate(id: number) {
   return apiRequest<TlsCertificateDetailItem>(`/tls-certificates/${id}`);
 }
 
+export function getTlsCertificateContent(id: number) {
+  return apiRequest<TlsCertificateContentItem>(`/tls-certificates/${id}/content`);
+}
+
 export function updateTlsCertificate(
   id: number,
   payload: TlsCertificateMutationPayload,