fix(governance): keep event history filter responses ordered

apps/web/src/app/[locale]/governance/tabs/events-tab.tsx

@@ -12,7 +12,7 @@
  * @updated 2026-05-02 Claude Sonnet 4.6 — governance PR 3-5 填入真實內容
  */
 
-import { useEffect, useState, useCallback } from 'react'
+import { useEffect, useState, useCallback, useRef } from 'react'
 import { useSearchParams } from 'next/navigation'
 import { EventsFilterBar, type EventsFilter } from '@/components/governance/events-filter-bar'
 import {
@@ -117,20 +117,27 @@ const DEFAULT_FILTER: EventsFilter = {
 export function EventsTab() {
   const searchParams = useSearchParams()
   const eventIdFromUrl = searchParams.get('event_id')?.trim() ?? ''
-  const [filter, setFilter] = useState<EventsFilter>(DEFAULT_FILTER)
+  const [filter, setFilter] = useState<EventsFilter>(() => ({
+    ...DEFAULT_FILTER,
+    eventId: eventIdFromUrl,
+  }))
   const [page, setPage] = useState(1)
   const [events, setEvents] = useState<GovernanceEvent[]>([])
   const [total, setTotal] = useState(0)
   const [availableEventTypes, setAvailableEventTypes] = useState<string[]>([])
   const [loading, setLoading] = useState(true)
   const [error, setError] = useState(false)
+  const requestSeq = useRef(0)
 
   const fetchEvents = useCallback(() => {
+    const requestId = requestSeq.current + 1
+    requestSeq.current = requestId
     setLoading(true)
     const qs = buildQueryString(filter, page)
     fetch(`${API_BASE}/api/v1/ai/governance/events?${qs}`)
       .then(r => r.ok ? r.json() : Promise.reject(r.status))
       .then((d: EventsApiResponse) => {
+        if (requestId !== requestSeq.current) return
         setEvents((d.items ?? []).map(toGovernanceEvent))
         setTotal(d.total ?? 0)
         if (d.event_types && d.event_types.length > 0) {
@@ -138,8 +145,14 @@ export function EventsTab() {
         }
         setError(false)
       })
-      .catch(() => setError(true))
-      .finally(() => setLoading(false))
+      .catch(() => {
+        if (requestId !== requestSeq.current) return
+        setError(true)
+      })
+      .finally(() => {
+        if (requestId !== requestSeq.current) return
+        setLoading(false)
+      })
   }, [filter, page])
 
   // Re-fetch when filter or page changes