feat(06-03): add AdvisorPage, /advisor route, and TopBar link

- AdvisorPage: two-panel layout (sidebar + chat), streaming SSE tokens
- Sidebar: conversation list with refetchInterval 5s, New Chat button
- Chat: optimistic user messages, streaming cursor, model dropdown
- router.tsx: lazy AdvisorPage import + advisorRoute at /advisor
- TopBar.tsx: MessageSquare icon + Advisor link between Test and Scan
- AppShell.tsx: noPadding prop for full-height layouts

web/src/components/layout/AppShell.tsx

@@ -1,11 +1,17 @@
 import * as React from 'react'
 import { TopBar } from './TopBar'
 
-export function AppShell({ children }: { children: React.ReactNode }) {
+interface AppShellProps {
+  children: React.ReactNode
+  /** When true, removes default padding/max-width from the main content area */
+  noPadding?: boolean
+}
+
+export function AppShell({ children, noPadding = false }: AppShellProps) {
   return (
     <div className="min-h-screen bg-canvas flex flex-col">
       <TopBar />
-      <main className="flex-1 px-4 py-6 max-w-7xl mx-auto w-full">
+      <main className={noPadding ? 'flex-1 flex flex-col overflow-hidden' : 'flex-1 px-4 py-6 max-w-7xl mx-auto w-full'}>
         {children}
       </main>
     </div>

web/src/components/layout/TopBar.tsx

@@ -1,4 +1,4 @@
-import { Plus, QrCode, Cable } from 'lucide-react'
+import { Plus, QrCode, Cable, MessageSquare } from 'lucide-react'
 import { Link } from '@tanstack/react-router'
 import { Button } from '@/components/ui/button'
 
@@ -9,6 +9,12 @@ export function TopBar() {
         HWLab
       </Link>
       <div className="flex items-center gap-2">
+        <Button variant="outline" size="sm" asChild>
+          <Link to="/advisor">
+            <MessageSquare className="w-4 h-4 mr-1.5" />
+            <span className="hidden sm:inline">Advisor</span>
+          </Link>
+        </Button>
         <Button variant="outline" size="sm" asChild>
           <Link to="/test">
             <Cable className="w-4 h-4 mr-1.5" />

web/src/pages/AdvisorPage.tsx

@@ -0,0 +1,288 @@
+import { useState, useRef, useEffect } from 'react'
+import { useQuery } from '@tanstack/react-query'
+import toast from 'react-hot-toast'
+import { Send, MessageSquare, Plus } from 'lucide-react'
+import { AppShell } from '@/components/layout/AppShell'
+import { Button } from '@/components/ui/button'
+import {
+  streamChat,
+  fetchConversations,
+  fetchConversation,
+  type ChatMessage,
+  type ConversationSummary,
+} from '@/api/advisor'
+
+const AVAILABLE_MODELS = [
+  'anthropic/claude-opus-4',
+  'anthropic/claude-sonnet-4-5',
+  'anthropic/claude-3-5-haiku',
+  'openai/gpt-4o',
+]
+
+const DEFAULT_MODEL = 'anthropic/claude-opus-4'
+
+function formatRelativeTime(dateStr: string): string {
+  const date = new Date(dateStr)
+  const now = new Date()
+  const diffMs = now.getTime() - date.getTime()
+  const diffMins = Math.floor(diffMs / 60000)
+  if (diffMins < 1) return 'just now'
+  if (diffMins < 60) return `${diffMins}m ago`
+  const diffHours = Math.floor(diffMins / 60)
+  if (diffHours < 24) return `${diffHours}h ago`
+  const diffDays = Math.floor(diffHours / 24)
+  return `${diffDays}d ago`
+}
+
+export function AdvisorPage() {
+  const [messages, setMessages] = useState<ChatMessage[]>([])
+  const [streamingContent, setStreamingContent] = useState('')
+  const [isStreaming, setIsStreaming] = useState(false)
+  const [currentConversationId, setCurrentConversationId] = useState<string | undefined>()
+  const [selectedModel, setSelectedModel] = useState(DEFAULT_MODEL)
+  const [input, setInput] = useState('')
+  const [selectedSidebarId, setSelectedSidebarId] = useState<string | undefined>()
+
+  // Use a ref to capture latest streamingContent inside async callback
+  const streamingContentRef = useRef('')
+  const messagesEndRef = useRef<HTMLDivElement>(null)
+  const textareaRef = useRef<HTMLTextAreaElement>(null)
+
+  const conversationsQuery = useQuery({
+    queryKey: ['advisor-conversations'],
+    queryFn: fetchConversations,
+    refetchInterval: 5000,
+  })
+
+  const conversationQuery = useQuery({
+    queryKey: ['advisor-conversation', selectedSidebarId],
+    queryFn: () => fetchConversation(selectedSidebarId!),
+    enabled: !!selectedSidebarId,
+  })
+
+  // Load messages when a sidebar conversation is selected
+  useEffect(() => {
+    if (conversationQuery.data && selectedSidebarId) {
+      setMessages(conversationQuery.data.messages)
+      setCurrentConversationId(selectedSidebarId)
+      setStreamingContent('')
+    }
+  }, [conversationQuery.data, selectedSidebarId])
+
+  // Scroll to bottom when messages or streaming content changes
+  useEffect(() => {
+    messagesEndRef.current?.scrollIntoView({ behavior: 'smooth' })
+  }, [messages, streamingContent])
+
+  function handleNewChat() {
+    setMessages([])
+    setCurrentConversationId(undefined)
+    setStreamingContent('')
+    streamingContentRef.current = ''
+    setInput('')
+    setSelectedSidebarId(undefined)
+    textareaRef.current?.focus()
+  }
+
+  function handleSelectConversation(conv: ConversationSummary) {
+    if (isStreaming) return
+    setSelectedSidebarId(conv.id)
+  }
+
+  async function handleSend() {
+    const trimmed = input.trim()
+    if (!trimmed || isStreaming) return
+
+    const userMessage: ChatMessage = {
+      id: crypto.randomUUID(),
+      role: 'user',
+      content: trimmed,
+      created_at: new Date().toISOString(),
+    }
+
+    setMessages((prev) => [...prev, userMessage])
+    setInput('')
+    setIsStreaming(true)
+    setStreamingContent('')
+    streamingContentRef.current = ''
+
+    await streamChat(
+      {
+        conversationId: currentConversationId,
+        message: trimmed,
+        model: selectedModel,
+      },
+      (token, convId) => {
+        streamingContentRef.current += token
+        setStreamingContent(streamingContentRef.current)
+        setCurrentConversationId(convId)
+      },
+      () => {
+        // onDone — finalize assistant message
+        const assistantMessage: ChatMessage = {
+          id: crypto.randomUUID(),
+          role: 'assistant',
+          content: streamingContentRef.current,
+          created_at: new Date().toISOString(),
+        }
+        setMessages((prev) => [...prev, assistantMessage])
+        setStreamingContent('')
+        streamingContentRef.current = ''
+        setIsStreaming(false)
+        // Refresh sidebar conversation list
+        conversationsQuery.refetch().catch(() => {})
+      },
+      (err) => {
+        toast.error(err)
+        setIsStreaming(false)
+        setStreamingContent('')
+        streamingContentRef.current = ''
+      },
+    )
+  }
+
+  function handleKeyDown(e: React.KeyboardEvent<HTMLTextAreaElement>) {
+    if (e.key === 'Enter' && !e.shiftKey) {
+      e.preventDefault()
+      handleSend()
+    }
+  }
+
+  const allMessages = messages
+
+  return (
+    <AppShell noPadding>
+      <div className="flex h-[calc(100vh-57px)]">
+        {/* Left sidebar */}
+        <aside className="hidden lg:flex flex-col w-[280px] flex-shrink-0 border-r border-charcoal/60 bg-[#0a0a0a] overflow-hidden">
+          <div className="p-4 border-b border-charcoal/60">
+            <h2 className="text-volt font-bold text-lg mb-3">Lab Advisor</h2>
+            <Button
+              variant="outline"
+              size="sm"
+              className="w-full"
+              onClick={handleNewChat}
+            >
+              <Plus className="w-4 h-4 mr-1.5" />
+              New Chat
+            </Button>
+          </div>
+
+          <div className="flex-1 overflow-y-auto">
+            {conversationsQuery.isLoading && (
+              <p className="text-[#666] text-xs text-center py-4">Loading...</p>
+            )}
+            {conversationsQuery.data?.length === 0 && (
+              <p className="text-[#666] text-xs text-center py-4 px-3">
+                No conversations yet
+              </p>
+            )}
+            {conversationsQuery.data?.map((conv) => (
+              <button
+                key={conv.id}
+                onClick={() => handleSelectConversation(conv)}
+                className={`w-full text-left px-4 py-3 border-b border-charcoal/30 hover:bg-[#111] transition-colors ${
+                  selectedSidebarId === conv.id ? 'bg-[#1a1a1a]' : ''
+                }`}
+              >
+                <div className="flex items-center gap-2 mb-1">
+                  <MessageSquare className="w-3 h-3 text-volt flex-shrink-0" />
+                  <span className="text-[#e0e0e0] text-xs font-medium truncate">
+                    {conv.model.split('/').pop()}
+                  </span>
+                </div>
+                <div className="flex items-center justify-between">
+                  <span className="text-[#666] text-xs">
+                    {conv.message_count} msg{conv.message_count !== 1 ? 's' : ''}
+                  </span>
+                  <span className="text-[#555] text-xs">
+                    {formatRelativeTime(conv.started_at)}
+                  </span>
+                </div>
+              </button>
+            ))}
+          </div>
+        </aside>
+
+        {/* Main chat panel */}
+        <main className="flex flex-col flex-1 min-w-0">
+          {/* Messages area */}
+          <div className="flex-1 overflow-y-auto p-4 space-y-4">
+            {allMessages.length === 0 && !streamingContent && (
+              <div className="flex flex-col items-center justify-center h-full gap-3 text-center">
+                <MessageSquare className="w-12 h-12 text-[#333]" />
+                <p className="text-[#666] text-sm">Ask anything about your homelab</p>
+              </div>
+            )}
+
+            {allMessages.map((msg) => (
+              <div
+                key={msg.id}
+                className={`flex ${msg.role === 'user' ? 'justify-end' : 'justify-start'}`}
+              >
+                <div
+                  className={`rounded-lg p-3 max-w-[80%] text-sm whitespace-pre-wrap break-words ${
+                    msg.role === 'user'
+                      ? 'bg-[#1a1a1a] text-white'
+                      : 'bg-[#111] text-[#e0e0e0]'
+                  }`}
+                >
+                  {msg.content}
+                </div>
+              </div>
+            ))}
+
+            {/* Streaming assistant message */}
+            {streamingContent && (
+              <div className="flex justify-start">
+                <div className="rounded-lg p-3 max-w-[80%] text-sm whitespace-pre-wrap break-words bg-[#111] text-[#e0e0e0]">
+                  {streamingContent}
+                  <span className="inline-block w-0.5 h-4 bg-volt ml-0.5 animate-pulse align-text-bottom" />
+                </div>
+              </div>
+            )}
+
+            <div ref={messagesEndRef} />
+          </div>
+
+          {/* Input row */}
+          <div className="border-t border-charcoal/60 p-4 flex gap-2 items-end">
+            <select
+              value={selectedModel}
+              onChange={(e) => setSelectedModel(e.target.value)}
+              disabled={isStreaming}
+              className="bg-[#111] border border-charcoal/60 text-[#e0e0e0] text-xs rounded-md px-2 py-2 focus:outline-none focus:border-volt/50 disabled:opacity-50 shrink-0"
+            >
+              {AVAILABLE_MODELS.map((m) => (
+                <option key={m} value={m}>
+                  {m.split('/').pop()}
+                </option>
+              ))}
+            </select>
+
+            <textarea
+              ref={textareaRef}
+              value={input}
+              onChange={(e) => setInput(e.target.value)}
+              onKeyDown={handleKeyDown}
+              rows={2}
+              disabled={isStreaming}
+              placeholder="Ask about your homelab..."
+              className="flex-1 bg-[#111] border border-charcoal/60 text-white text-sm rounded-md px-3 py-2 resize-none focus:outline-none focus:border-volt/50 placeholder-[#555] disabled:opacity-50"
+            />
+
+            <Button
+              variant="forest"
+              size="sm"
+              onClick={handleSend}
+              disabled={isStreaming || !input.trim()}
+              className="shrink-0 self-end"
+            >
+              <Send className="w-4 h-4" />
+            </Button>
+          </div>
+        </main>
+      </div>
+    </AppShell>
+  )
+}

web/src/router.tsx

@@ -7,6 +7,7 @@ const ItemDetailPage = lazy(() => import('./pages/ItemDetailPage').then((m) => (
 const IntakePage = lazy(() => import('./pages/IntakePage').then((m) => ({ default: m.IntakePage })))
 const ScanPage = lazy(() => import('./pages/ScanPage').then((m) => ({ default: m.ScanPage })))
 const CableTestPage = lazy(() => import('./pages/CableTestPage').then((m) => ({ default: m.CableTestPage })))
+const AdvisorPage = lazy(() => import('./pages/AdvisorPage').then((m) => ({ default: m.AdvisorPage })))
 
 const Spinner = () => (
   <div className="min-h-screen bg-canvas flex items-center justify-center">
@@ -74,7 +75,17 @@ const cableTestRoute = createRoute({
   ),
 })
 
-const routeTree = rootRoute.addChildren([indexRoute, itemRoute, intakeRoute, scanRoute, cableTestRoute])
+const advisorRoute = createRoute({
+  getParentRoute: () => rootRoute,
+  path: '/advisor',
+  component: () => (
+    <Suspense fallback={<Spinner />}>
+      <AdvisorPage />
+    </Suspense>
+  ),
+})
+
+const routeTree = rootRoute.addChildren([indexRoute, itemRoute, intakeRoute, scanRoute, cableTestRoute, advisorRoute])
 
 export const router = createRouter({
   routeTree,