fix(#75): preserve Race Hub meeting/session on Weekend return

Add an explicit Back to Weekend link that deep-links to /?meeting_key&session_key,
restore that focus on the adaptive Weekend home with a Continue analysis CTA, and
regenerate Race Hub visual baselines against the integrated #80 nav.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/test/RaceHubPage.test.tsx

@@ -243,6 +243,19 @@ function renderRaceHub(sessionKey: number) {
       </QueryClientProvider>
     ),
   })
+  const weekendRoute = createRoute({
+    getParentRoute: () => rootRoute,
+    path: '/',
+    validateSearch: (search: Record<string, unknown>) => {
+      const meetingKey = Number(search.meeting_key)
+      const sk = Number(search.session_key)
+      return {
+        ...(Number.isFinite(meetingKey) && meetingKey > 0 ? { meeting_key: meetingKey } : {}),
+        ...(Number.isFinite(sk) && sk > 0 ? { session_key: sk } : {}),
+      }
+    },
+    component: () => <div data-testid="weekend-stub" />,
+  })
   const raceHubRoute = createRoute({
     getParentRoute: () => rootRoute,
     path: '/race-hub',
@@ -256,7 +269,7 @@ function renderRaceHub(sessionKey: number) {
     },
   })
   const router = createRouter({
-    routeTree: rootRoute.addChildren([raceHubRoute]),
+    routeTree: rootRoute.addChildren([weekendRoute, raceHubRoute]),
     history: undefined,
   })
 
@@ -541,10 +554,22 @@ describe('RaceHubPage', () => {
     await waitFor(() => expect(screen.getByTestId('race-hub-error')).toBeInTheDocument())
     expect(screen.getByTestId('rh-retry')).toBeInTheDocument()
     const back = screen.getByTestId('rh-back-weekend')
-    expect(back).toHaveAttribute('href', '/race-hub?session_key=9472')
+    expect(back).toHaveAttribute('href', expect.stringMatching(/meeting_key=1229/))
+    expect(back).toHaveAttribute('href', expect.stringMatching(/session_key=9472/))
+    expect(back.getAttribute('href')).toMatch(/^\//)
 
     mockFetchRaceHub.mockResolvedValue(raceHub)
     fireEvent.click(screen.getByTestId('rh-retry'))
     await waitFor(() => expect(screen.getByTestId('race-hub')).toBeInTheDocument())
   })
+
+  it('exposes a Back to Weekend link that carries meeting and session context', async () => {
+    renderRaceHub(9472)
+
+    await waitFor(() => expect(screen.getByTestId('race-hub')).toBeInTheDocument())
+    const back = screen.getByRole('link', { name: 'Back to Weekend' })
+    expect(back).toHaveAttribute('data-testid', 'rh-back-weekend')
+    expect(back).toHaveAttribute('href', expect.stringMatching(/meeting_key=1229/))
+    expect(back).toHaveAttribute('href', expect.stringMatching(/session_key=9472/))
+  })
 })

frontend/src/test/WeekendPage.test.tsx

@@ -20,12 +20,14 @@ import type {
   TemporalState,
   WeekendContext,
 } from '../types'
+import { parseWeekendSearch } from '../lib/routeSearch'
 
 vi.mock('../api', () => ({
   fetchWeekendContext: vi.fn(),
   fetchChampionshipHub: vi.fn(),
   fetchNews: vi.fn(),
   fetchRaceHub: vi.fn(),
+  fetchWeekend: vi.fn(),
   // Consumed transitively by RacePreviewPage (folded into PreSessionView):
   fetchSeasons: vi.fn(),
   fetchMeetings: vi.fn(),
@@ -40,6 +42,7 @@ import {
   fetchChampionshipHub,
   fetchNews,
   fetchRaceHub,
+  fetchWeekend,
   fetchSeasons,
   fetchMeetings,
   fetchSessions,
@@ -52,6 +55,7 @@ const mockContext = vi.mocked(fetchWeekendContext)
 const mockHub = vi.mocked(fetchChampionshipHub)
 const mockNews = vi.mocked(fetchNews)
 const mockRaceHub = vi.mocked(fetchRaceHub)
+const mockWeekend = vi.mocked(fetchWeekend)
 const mockSeasons = vi.mocked(fetchSeasons)
 const mockMeetings = vi.mocked(fetchMeetings)
 const mockSessions = vi.mocked(fetchSessions)
@@ -152,7 +156,15 @@ function renderAt(path: string) {
       </QueryClientProvider>
     ),
   })
-  const homeRoute = createRoute({ getParentRoute: () => rootRoute, path: '/', component: () => <WeekendPage /> })
+  const homeRoute = createRoute({
+    getParentRoute: () => rootRoute,
+    path: '/',
+    validateSearch: (s: Record<string, unknown>) => parseWeekendSearch(s),
+    component: function HomeRoute() {
+      const { meeting_key, session_key } = homeRoute.useSearch()
+      return <WeekendPage focusMeetingKey={meeting_key} focusSessionKey={session_key} />
+    },
+  })
   const previewRoute = createRoute({
     getParentRoute: () => rootRoute,
     path: '/preview',
@@ -192,6 +204,19 @@ describe('WeekendPage canonical contract rendering', () => {
     mockHub.mockResolvedValue(hub)
     mockNews.mockResolvedValue([])
     mockRaceHub.mockResolvedValue(raceHub)
+    mockWeekend.mockResolvedValue({
+      source: 'local',
+      meeting_key: 1,
+      meeting: meeting(),
+      sessions: [
+        {
+          session: session({ session_key: 11, session_name: 'Race' }),
+          source: 'local',
+          datasets: {},
+        },
+      ],
+      default_session_key: 11,
+    })
     mockSeasons.mockResolvedValue([2026])
     mockMeetings.mockResolvedValue([meeting()])
     mockSessions.mockResolvedValue([session()])
@@ -306,4 +331,27 @@ describe('WeekendPage canonical contract rendering', () => {
     // The between-races surface must NOT be what /preview renders.
     expect(screen.queryByTestId('weekend-between-races')).not.toBeInTheDocument()
   })
+
+  it('restores Race Hub meeting/session focus from the Weekend URL search contract', async () => {
+    mockContext.mockResolvedValue(
+      context({
+        temporal_state: 'season_complete',
+        previous_completed_session: ctxSession({ session: session({ session_key: 11, session_name: 'Race' }) }),
+        default_analysis_session: ctxSession({ session: session({ session_key: 11 }) }),
+      }),
+    )
+    renderAt('/?meeting_key=1&session_key=11')
+    await waitFor(() => expect(screen.getByTestId('wk-focus-context')).toBeInTheDocument())
+    expect(screen.getByTestId('weekend-page')).toHaveAttribute('data-meeting-key', '1')
+    expect(screen.getByTestId('weekend-page')).toHaveAttribute('data-session-key', '11')
+    await waitFor(() =>
+      expect(screen.getByTestId('wk-focus-meeting')).toHaveTextContent('British Grand Prix'),
+    )
+    await waitFor(() =>
+      expect(screen.getByTestId('wk-focus-session')).toHaveTextContent('Race'),
+    )
+    const continueAnalysis = screen.getByRole('link', { name: /Continue analysis/i })
+    expect(continueAnalysis).toHaveAttribute('href', expect.stringContaining('session_key=11'))
+    expect(mockWeekend).toHaveBeenCalledWith(1)
+  })
 })

frontend/src/test/routeSearch.test.ts

@@ -0,0 +1,24 @@
+import { describe, it, expect } from 'vitest'
+import { parseRaceHubSearch, parseWeekendSearch, weekendFocusSearch } from '../lib/routeSearch'
+
+describe('routeSearch', () => {
+  it('parses positive weekend meeting/session keys and drops invalid values', () => {
+    expect(parseWeekendSearch({ meeting_key: '1229', session_key: '9000' })).toEqual({
+      meeting_key: 1229,
+      session_key: 9000,
+    })
+    expect(parseWeekendSearch({ meeting_key: '0', session_key: '-1', foo: 'bar' })).toEqual({})
+    expect(parseWeekendSearch({})).toEqual({})
+  })
+
+  it('parses race-hub session keys', () => {
+    expect(parseRaceHubSearch({ session_key: '9472' })).toEqual({ session_key: 9472 })
+    expect(parseRaceHubSearch({ session_key: 'nope' })).toEqual({})
+  })
+
+  it('builds Weekend focus search for Race Hub returns', () => {
+    expect(weekendFocusSearch(1229, 9000)).toEqual({ meeting_key: 1229, session_key: 9000 })
+    expect(weekendFocusSearch(null, 9000)).toEqual({ session_key: 9000 })
+    expect(weekendFocusSearch(1229, undefined)).toEqual({ meeting_key: 1229 })
+  })
+})