feat: extend cluster k8s_options with multi-vendor manifest support

- New k8s_pod_spec form sections (image credentials, node selector,
  gpu vendor overrides) under k8s_options, replacing the legacy flat
  k8s_volume_mounts list. UI keys aligned to the backend wire shape
  (snake_case k8s_options + camelCase inside).
- System default container registry is pre-filled into the first image
  credential when creating a new cluster; empty username/password are
  coerced to null on submit to match the Optional[str] backend schema.
- Register cluster flow supports multi-runtime selection gated by the
  cluster's gpuVendorOverrides: non-override vendors stay single-select
  with an inline hint; multi-add only opens once an override vendor is
  picked, and non-override cards become disabled in that state.
- Manifest URL emits multiple ?runtime= params; check-env step combines
  per-vendor commands; downstream steps are disabled when no vendor is
  selected.
- Pre-validate gpuVendorOverrides at save time (non-empty selector, no
  duplicates across vendors, no key clash with base nodeSelector) so
  the user sees the error before hitting the manifest endpoint.
- Misc: dark-mode background of the k8s_pod_spec / volume mount titles
  no longer clashes with the drawer; cluster Steps no longer leaks the
  internal showModules/showForms props to the DOM.

src/pages/cluster-management/step-forms/advance-config.tsx

@@ -7,9 +7,13 @@ import { useIntl } from '@umijs/max';
 import { Button, Form } from 'antd';
 import React, { forwardRef, useEffect, useImperativeHandle } from 'react';
 import styled from 'styled-components';
+import K8sPodSpec from '../components/k8s-pod-spec';
 import K8SVolumeMount from '../components/k8s-volume-mount';
 import { ProviderType, ProviderValueMap } from '../config';
-import { ClusterFormData as FormData } from '../config/types';
+import {
+  ClusterFormData as FormData,
+  ClusterListItem as ListItem
+} from '../config/types';
 import schema from '../config/worker-config.json';
 import { dockerConfig, kubernetesConfig } from '../config/yaml-template';
 
@@ -28,8 +32,9 @@ const Title = styled.div`
 const ClusterAdvanceConfig: React.FC<{
   action: PageActionType;
   provider: ProviderType;
+  currentData?: ListItem;
   ref?: any;
-}> = forwardRef(({ action, provider }, ref) => {
+}> = forwardRef(({ action, provider, currentData }, ref) => {
   const [form] = Form.useForm();
   const intl = useIntl();
   const editorRef = React.useRef<any>(null);
@@ -75,7 +80,12 @@ const ClusterAdvanceConfig: React.FC<{
         <CInput.TextArea required={false} trim={false}></CInput.TextArea>
       </Form.Item>
       {provider === ProviderValueMap.Kubernetes && (
-        <K8SVolumeMount action={action}></K8SVolumeMount>
+        <>
+          <K8SVolumeMount action={action}></K8SVolumeMount>
+          <K8sPodSpec
+            initialOverrides={currentData?.k8s_options?.gpuVendorOverrides}
+          ></K8sPodSpec>
+        </>
       )}
       <Title>
         {intl.formatMessage({ id: 'clusters.create.workerConfig' })}