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/AtlasChat.tsx

@@ -151,7 +151,7 @@ function MessageRow({
           marginBottom: 5, textTransform: "uppercase", letterSpacing: "0.04em",
           fontFamily: "Outfit, sans-serif",
         }}>
-          {isAtlas ? "Atlas" : "You"}
+          {isAtlas ? "Vibn" : "You"}
         </div>
         {/* Content */}
         <div style={{
@@ -448,7 +448,7 @@ export function AtlasChat({ projectId }: AtlasChatProps) {
           }}>A</div>
           <style>{`@keyframes breathe { 0%,100%{transform:scale(1)} 50%{transform:scale(1.08)} }`}</style>
           <div style={{ textAlign: "center" }}>
-            <p style={{ fontSize: "0.88rem", fontWeight: 600, color: "#1a1a1a", marginBottom: 4 }}>Atlas</p>
+            <p style={{ fontSize: "0.88rem", fontWeight: 600, color: "#1a1a1a", marginBottom: 4 }}>Vibn</p>
             <p style={{ fontSize: "0.78rem", color: "#a09a90", maxWidth: 260, lineHeight: 1.5 }}>
               Your product strategist. Let&apos;s define what you&apos;re building.
             </p>