feat(ai): 全站 AI 助手浮窗(参考 FlowStack 右下角浮空设计)

- POST /ai/chat:多轮对话(messages 透传)+ 页面上下文注入 —— 前端带当前路径,
  后端自动附加该数据源近 15 分钟轻量日志摘要(总量/Top3 应用/告警命中),
  追问「这个报错什么原因」有数据依据;脱敏/每日配额/Pro 闸门与整页分析共用
- AiAssistant 浮球+浮窗挂 Layout:仅 admin+Pro 渲染;消息气泡、Enter 发送、
  上下文随路由自动采集;免费版不显示

frontend/src/api/ai/index.ts

@@ -91,4 +91,7 @@ export const aiApi = {
       `/ai/runs?page=${page}&pageSize=${pageSize}`,
     ),
   run: (id: number) => http.get<AIRun>(`/ai/runs/${id}`),
+
+  chat: (data: { sourceId?: number; history: Array<{ role: 'user' | 'assistant'; content: string }>; page?: string; rangeMinutes?: number }) =>
+    http.post<{ reply: string }>('/ai/chat', data),
 }

frontend/src/components/AiAssistant.tsx

@@ -0,0 +1,124 @@
+import { memo, useEffect, useRef, useState } from 'react'
+import { useLocation } from 'react-router'
+import { useTranslation } from 'react-i18next'
+import { Loader2, Send, Sparkles, X } from 'lucide-react'
+import { Button } from '@/components/ui/button'
+import { Textarea } from '@/components/ui/textarea'
+import { aiApi } from '@/api/ai'
+import { getUser } from '@/lib/auth-storage'
+import { useLicense } from '@/hooks/useLicense'
+
+interface Msg { role: 'user' | 'assistant'; content: string }
+
+/**
+ * 全站 AI 助手浮窗(参考 FlowStack 右下角浮空设计):
+ * 仅管理员 + Pro 生效时渲染;对话自动携带当前页面路径作为上下文,
+ * 后端按需注入当前数据源的日志摘要,让"现在这个报错是什么"有数据依据。
+ */
+export const AiAssistant = memo(function AiAssistant() {
+  const { t } = useTranslation('aiops')
+  const location = useLocation()
+  const { pro } = useLicense()
+  const isAdmin = getUser()?.role === 'admin'
+  const [open, setOpen] = useState(false)
+  const [messages, setMessages] = useState<Msg[]>([])
+  const [input, setInput] = useState('')
+  const [sending, setSending] = useState(false)
+  const listRef = useRef<HTMLDivElement>(null)
+
+  useEffect(() => {
+    if (listRef.current) listRef.current.scrollTop = listRef.current.scrollHeight
+  }, [messages, sending])
+
+  if (!isAdmin || !pro) return null
+
+  const send = async () => {
+    const text = input.trim()
+    if (!text || sending) return
+    const next: Msg[] = [...messages, { role: 'user', content: text }]
+    setMessages(next)
+    setInput('')
+    setSending(true)
+    try {
+      const res = await aiApi.chat({
+        history: next.slice(-20),
+        page: location.pathname,
+        rangeMinutes: 15,
+      })
+      setMessages(current => [...current, { role: 'assistant', content: res.reply }])
+    } catch (err) {
+      setMessages(current => [...current, { role: 'assistant', content: err instanceof Error ? err.message : t('assistant.error') }])
+    } finally {
+      setSending(false)
+    }
+  }
+
+  return (
+    <>
+      <button
+        type="button"
+        aria-label={open ? t('assistant.close') : t('assistant.open')}
+        onClick={() => setOpen(!open)}
+        className="fixed bottom-6 right-6 z-50 flex size-12 items-center justify-center rounded-full bg-primary text-primary-foreground shadow-lg transition-transform hover:scale-105"
+      >
+        {open ? <X className="size-5" /> : <Sparkles className="size-5" />}
+      </button>
+      {open && (
+        <div
+          className="fixed bottom-20 right-6 z-50 flex h-[520px] w-[min(92vw,400px)] flex-col overflow-hidden rounded-xl border bg-card shadow-2xl"
+          role="dialog"
+          aria-label={t('assistant.title')}
+        >
+          <div className="flex items-center justify-between border-b px-4 py-2.5">
+            <span className="flex items-center gap-2 text-sm font-semibold">
+              <Sparkles className="size-4 text-primary" />
+              {t('assistant.title')}
+            </span>
+            <button type="button" aria-label={t('assistant.close')} onClick={() => setOpen(false)} className="rounded p-1 text-muted-foreground hover:bg-muted">
+              <X className="size-4" />
+            </button>
+          </div>
+          <div ref={listRef} className="flex-1 space-y-3 overflow-y-auto p-4 text-sm">
+            {messages.length === 0 && (
+              <p className="py-8 text-center text-xs text-muted-foreground">{t('assistant.emptyHint')}</p>
+            )}
+            {messages.map((m, i) => (
+              <div key={i} className={m.role === 'user' ? 'flex justify-end' : 'flex justify-start'}>
+                <div className={
+                  m.role === 'user'
+                    ? 'max-w-[85%] rounded-lg bg-primary px-3 py-2 text-primary-foreground'
+                    : 'max-w-[85%] whitespace-pre-wrap rounded-lg bg-muted px-3 py-2'
+                }>
+                  {m.content}
+                </div>
+              </div>
+            ))}
+            {sending && (
+              <div className="flex justify-start">
+                <div className="flex items-center gap-2 rounded-lg bg-muted px-3 py-2 text-xs text-muted-foreground">
+                  <Loader2 className="size-3.5 animate-spin" />
+                  {t('assistant.thinking')}
+                </div>
+              </div>
+            )}
+          </div>
+          <div className="flex items-end gap-2 border-t p-3">
+            <Textarea
+              rows={1}
+              value={input}
+              onChange={e => setInput(e.target.value)}
+              onKeyDown={e => {
+                if (e.key === 'Enter' && !e.shiftKey) { e.preventDefault(); void send() }
+              }}
+              placeholder={t('assistant.placeholder')}
+              className="max-h-28 min-h-9 resize-none text-sm"
+            />
+            <Button size="sm" onClick={() => void send()} disabled={sending || !input.trim()} aria-label={t('assistant.send')}>
+              <Send className="size-4" />
+            </Button>
+          </div>
+        </div>
+      )}
+    </>
+  )
+})

frontend/src/components/Layout.tsx

@@ -22,6 +22,7 @@ import { cn } from '@/lib/utils'
 import { useIsMobile } from '@/hooks/use-mobile'
 import { menuItems, findRouteMeta, findGroupKey } from '@/router/routes'
 import { useLicense } from '@/hooks/useLicense'
+import { AiAssistant } from '@/components/AiAssistant'
 import { Lock } from 'lucide-react'
 import { GroupTabs } from './GroupTabs'
 import { getUser, clearAuth } from '@/lib/auth-storage'
@@ -265,9 +266,10 @@ const Layout = memo(function Layout({ children }: { children: React.ReactNode })
         <main className="flex-1 overflow-auto p-4 md:p-6">
           <Suspense fallback={<PageSkeleton />}>{children}</Suspense>
         </main>
+        <AiAssistant />
       </div>
     </div>
   )
 })
 
-export default Layout
+export default Layout

frontend/src/i18n/locales/en/aiops.ts

@@ -1,4 +1,15 @@
 export default {
+  assistant: {
+    title: 'AI Assistant',
+    open: 'Open AI assistant',
+    close: 'Close',
+    send: 'Send',
+    thinking: 'Thinking…',
+    error: 'Request failed',
+    placeholder: 'Ask about logs, e.g. anything unusual now?',
+    emptyHint: 'Just ask; I can see the page you are viewing and the last 15 minutes of logs.',
+  },
+
   title: 'AIOps',
   subtitle: 'Let a model read log signals: statistics first, conclusions second — raw logs never leave the platform',
 

frontend/src/i18n/locales/zh/aiops.ts

@@ -1,4 +1,15 @@
 export default {
+  assistant: {
+    title: 'AI 助手',
+    open: '打开 AI 助手',
+    close: '关闭',
+    send: '发送',
+    thinking: '思考中…',
+    error: '请求失败',
+    placeholder: '问问日志的事,如:当前有什么异常?',
+    emptyHint: '直接提问;我会参考你当前正在查看的页面与近 15 分钟日志概况。',
+  },
+
   title: '智能运维',
   subtitle: '用大模型解读日志信号：先看统计、再看结论，全程不把日志原文发出去',