Set CauseStarter tab title from domain branding

ui/src/App.test.tsx

@@ -14,6 +14,12 @@ vi.mock('./shared/routing/routing', () => ({
   getAppUrl: vi.fn(),
 }))
 
+vi.mock('./causestarter/shell/CauseShell', () => ({
+  CauseShell: ({ children }: { children: React.ReactNode }) => (
+    <div data-testid="cause-shell">{children}</div>
+  ),
+}))
+
 vi.mock('./shared/components/AppShell', () => ({
   AppShell: ({ branding, navigation, children }: { branding: { name: string }; navigation: { primaryNavigation: Array<{label: string; path: string}>; secondaryNavigation: Array<{label: string; path: string}>; footerText: string }; children: React.ReactNode }) => (
     <div data-testid="app-shell">
@@ -134,6 +140,28 @@ describe('App route composition', () => {
 
       expect(screen.getByText('Common Sense Majority')).toBeInTheDocument()
     })
+
+    it('sets the document title from domain branding', async () => {
+      mockGetActiveDomain.mockReturnValue(fakeDomain('CauseStarter', [], 'footer'))
+
+      const { default: App } = await import('./App')
+      render(React.createElement(App))
+
+      expect(document.title).toBe('CauseStarter')
+    })
+
+    it('sets the document title when using CauseShell', async () => {
+      mockGetActiveDomain.mockReturnValue({
+        ...fakeDomain('CauseStarter', [], 'footer'),
+        useCauseShell: true,
+      })
+
+      const { default: App } = await import('./App')
+      render(React.createElement(App))
+
+      expect(screen.getByTestId('cause-shell')).toBeInTheDocument()
+      expect(document.title).toBe('CauseStarter')
+    })
   })
 
   describe('primary navigation per domain', () => {

ui/src/App.tsx

@@ -9,6 +9,11 @@ import { CauseShell } from './causestarter/shell/CauseShell'
 
 function DomainChrome({ children }: { children: ReactNode }) {
   const domain = getActiveDomain()
+
+  useEffect(() => {
+    document.title = domain.branding.name
+  }, [domain.branding.name])
+
   if (domain.useCauseShell) {
     return <CauseShell>{children}</CauseShell>
   }

ui/src/shared/components/AppShell.tsx

@@ -1,4 +1,4 @@
-import { useState, useEffect } from 'react'
+import { useState } from 'react'
 import type { MouseEvent, ReactNode } from 'react'
 import {
   AppBar,
@@ -208,10 +208,6 @@ export function AppShell({ children, branding, navigation }: AppShellProps) {
     tagline: 'Find common ground and fund what matters.',
   }
 
-  useEffect(() => {
-    document.title = brand.name
-  }, [brand.name])
-
   const nav = navigation ?? {
     primaryNavigation: [
       { label: 'Start Here', path: '/docs' },

ui/vite.config.ts

@@ -18,7 +18,7 @@ export default defineConfig(({ mode }) => {
   build: {
     outDir: `dist/${domain}`,
   },
-  plugins: [react(), runtimeConfigPlugin(domain, env), endUserDocsPlugin({ domain })],
+  plugins: [react(), htmlTitlePlugin(domain), runtimeConfigPlugin(domain, env), endUserDocsPlugin({ domain })],
   worker: {
     format: 'es',
   },
@@ -102,6 +102,29 @@ function sdkSourceAliases(): Record<string, string> {
   )
 }
 
+// Must match branding.name in ui/src/domains/*/manifest.tsx (Vite cannot import those TSX files here).
+const DOMAIN_TITLES: Record<string, string> = {
+  commonality: 'Commonality',
+  lazyGiving: 'LazyGiving',
+  alignment: 'Aligning',
+  tally: 'Tally',
+  'content-funding': 'Content Funding',
+  civility: 'Civility',
+  'common-sense-majority': 'Common Sense Majority',
+  conceptspace: 'Conceptspace',
+  causestarter: 'CauseStarter',
+}
+
+function htmlTitlePlugin(buildDomain: string): Plugin {
+  const title = DOMAIN_TITLES[buildDomain] ?? 'Commonality'
+  return {
+    name: 'commonality-html-title',
+    transformIndexHtml(html) {
+      return html.replace(/<title>[^<]*<\/title>/, `<title>${title}</title>`)
+    },
+  }
+}
+
 function runtimeConfigPlugin(buildDomain: string, env: Record<string, string>): Plugin {
   return {
     name: 'commonality-runtime-config',