fix(logs): 域名筛选与残余原生 select 统一为可搜索/Radix Select

通病：/logs 域名筛选仍用 Input+datalist（与已修的快捷模板同类）；策略组数据源、数据源弹窗集群/鉴权仍为原生 select。改为 SearchableValueSelect / ui/select，并顺带理顺策略组列表空标签与用户勾选交互。采集器编辑里 app 预设 datalist 仍保留（自由输入场景）。

frontend/src/pages/logs/components/LogResultsPanel.tsx

@@ -2,7 +2,7 @@ import { useEffect, useMemo, useState } from 'react'
 import { Loader2 } from 'lucide-react'
 import { useTranslation } from 'react-i18next'
 import { Button } from '@/components/ui/button'
-import { Input } from '@/components/ui/input'
+import { SearchableValueSelect } from '@/components/SearchableValueSelect'
 import type { LogEntry } from '@/api/logs'
 import { parseIngressAccessLog } from '@/lib/ingress-access-log'
 import { applyLabelFilter } from '../query-utils'
@@ -50,9 +50,19 @@ export function LogResultsPanel({ entries, searched, hasSource, pageIndex, hasNe
     </div>}
     {pageIndex > 0 && <p className="mb-2 text-xs text-muted-foreground">{t('results.pagingHint')}</p>}
     {domains.length > 0 && <div className="mb-3 flex flex-wrap items-center gap-2 text-xs">
-      <label htmlFor="log-domain-filter" className="shrink-0 text-muted-foreground">{t('results.domainFilter')}</label>
-      <Input id="log-domain-filter" list="log-domain-options" type="search" className="h-8 w-60" value={domainFilter} onChange={event => setDomainFilter(event.target.value)} placeholder={t('results.domainPlaceholder')} />
-      <datalist id="log-domain-options">{domains.map(domain => <option key={domain} value={domain} />)}</datalist>
+      <span className="shrink-0 text-muted-foreground">{t('results.domainFilter')}</span>
+      <SearchableValueSelect
+        hideLabel
+        ariaLabel={t('results.domainFilter')}
+        values={domains}
+        value={domainFilter}
+        onChange={setDomainFilter}
+        allowEmpty
+        emptyLabel={t('results.domainAll')}
+        placeholder={t('results.domainPlaceholder')}
+        className="min-w-60"
+        triggerClassName="h-8"
+      />
       <Button type="button" size="sm" variant="outline" disabled={!domainFilter.trim() || loading} onClick={() => onApplyDomain(domainFilter.trim())}>{t('results.domainQuery')}</Button>
       <span className="text-muted-foreground">{t('results.domainHint', { shown: visibleEntries.length, total: entries.length })}</span>
     </div>}