chore(ambient-ui): rebrand user-facing text from Ambient to ACP (#1672)

## Summary

- Renames all user-facing "Ambient" / "Ambient Code Platform" strings to
"ACP" in the ambient-ui component
- 5 files, 7 lines changed — cosmetic only, no code identifiers or API
paths changed

### Files changed

| File | What changed |
|------|-------------|
| `layout.tsx` | Page title + meta description |
| `app-sidebar.tsx` | Sidebar brand label |
| `nav-header.tsx` | Breadcrumb root |
| `page.tsx` | Empty state message |
| `README.md` | Heading + description |

## Test plan

- [x] `npm run build` passes with zero errors and zero warnings

🤖 Generated with [Claude Code](https://claude.com/claude-code)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Documentation**
* Updated README reflecting product rebrand from "Ambient UI" to "ACP
UI."

* **Chores**
* Updated product name and descriptions throughout the application
interface, including page titles, sidebar branding, navigation headers,
and empty-state messaging.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Author: 3 people

components/ambient-ui/README.md

@@ -1,6 +1,6 @@
-# Ambient UI
+# ACP UI
 
-Operations console for the Ambient Code Platform. Next.js BFF with OIDC authentication (Keycloak), shadcn/ui components, and Red Hat design system.
+Operations console for ACP. Next.js BFF with OIDC authentication (Keycloak), shadcn/ui components, and Red Hat design system.
 
 ## Local Development
 

components/ambient-ui/src/app/(dashboard)/page.tsx

@@ -63,7 +63,7 @@ export default function ProjectPickerPage() {
         <EmptyState
           icon={FolderOpen}
           title="No projects found"
-          description="Create a project to get started with the Ambient Code Platform."
+          description="Create a project to get started with ACP."
         />
         <div className="flex justify-center">
           <CreateProjectDialog />

components/ambient-ui/src/app/layout.tsx

@@ -16,8 +16,8 @@ const redHatMono = Red_Hat_Mono({
 })
 
 export const metadata: Metadata = {
-  title: "Ambient UI",
-  description: "Ambient Code Platform operations console",
+  title: "ACP",
+  description: "Agent Control Plane operations console",
 }
 
 export default function RootLayout({

components/ambient-ui/src/components/app-sidebar.tsx

@@ -148,7 +148,7 @@ export function AppSidebar({ projectId }: AppSidebarProps) {
       <SidebarHeader>
         <div className="flex items-center gap-2 px-2 py-1.5">
           <Bot className="size-5 text-primary" />
-          <span className="text-sm font-semibold tracking-tight">Ambient</span>
+          <span className="text-sm font-semibold tracking-tight">ACP</span>
         </div>
         <ProjectSelector projectId={projectId} />
       </SidebarHeader>

components/ambient-ui/src/components/nav-header.tsx

@@ -122,7 +122,7 @@ export function NavHeader({ projectId, projectName, pageName, sessionName, detai
           <BreadcrumbItem>
             <BreadcrumbLink asChild>
               <Link href="/">
-                <span>Ambient</span>
+                <span>ACP</span>
               </Link>
             </BreadcrumbLink>
           </BreadcrumbItem>