rename: replace all user-facing 'Atlas' references with 'Vibn'

Updated UI text in: project-shell (tab label), AtlasChat (sender name),
FreshIdeaMain, TypeSelector, MigrateSetup, ChatImportSetup, FreshIdeaSetup,
CodeImportSetup, prd/page, build/page, projects/page, deployment/page,
activity/page, layout (page title/description), atlas-chat API route.
Code identifiers (AtlasChat component name, file names) unchanged.

Made-with: Cursor

components/project-creation/FreshIdeaSetup.tsx

@@ -80,11 +80,11 @@ export function FreshIdeaSetup({ workspace, onClose, onBack }: SetupProps) {
       />
 
       <div style={{ fontSize: "0.75rem", color: "#a09a90", marginBottom: 20, lineHeight: 1.5, padding: "12px 14px", background: "#faf8f5", borderRadius: 8, border: "1px solid #f0ece4" }}>
-        Atlas will guide you through 6 discovery phases — Big Picture, Users, Features, Business Model, Screens, and Risks — building your product plan as you go.
+        Vibn will guide you through 6 discovery phases — Big Picture, Users, Features, Business Model, Screens, and Risks — building your product plan as you go.
       </div>
 
       <PrimaryButton onClick={handleCreate} disabled={!canCreate} loading={loading}>
-        Start with Atlas →
+        Start with Vibn →
       </PrimaryButton>
     </div>
   );