Update UI color scheme from purple to teal

Change accent color palette to match Brainiac Chat Interface design:
- Replace purple accent colors with teal (#14B8A6 primary)
- Update favicon and logo SVGs with new teal gradient
- Update gradient colors in index.scss
- Update QR modal background color

Author: claude

app/components/workbench/ExpoQrModal.tsx

@@ -39,7 +39,7 @@ export const ExpoQrModal: React.FC<ExpoQrModalProps> = ({ open, onClose }) => {
                 style={{
                   borderRadius: 16,
                   padding: 2,
-                  backgroundColor: '#8a5fff',
+                  backgroundColor: '#0D9488',
                 }}
                 value={expoUrl}
                 size={200}

app/styles/index.scss

@@ -16,12 +16,9 @@ body {
 
 :root {
   --gradient-opacity: 0.8;
-  --primary-color: rgba(158, 117, 240, var(--gradient-opacity));
-  --secondary-color: rgba(138, 43, 226, var(--gradient-opacity));
-  --accent-color: rgba(128, 59, 239, var(--gradient-opacity));
-  // --primary-color: rgba(147, 112, 219, var(--gradient-opacity));
-  // --secondary-color: rgba(138, 43, 226, var(--gradient-opacity));
-  // --accent-color: rgba(180, 170, 220, var(--gradient-opacity));
+  --primary-color: rgba(20, 184, 166, var(--gradient-opacity));
+  --secondary-color: rgba(13, 148, 136, var(--gradient-opacity));
+  --accent-color: rgba(45, 212, 191, var(--gradient-opacity));
 }
 
 .modern-scrollbar {

public/favicon.svg

@@ -35,17 +35,17 @@ const BASE_COLORS = {
     950: '#0A0A0A',
   },
   accent: {
-    50: '#F8F5FF',
-    100: '#F0EBFF',
-    200: '#E1D6FF',
-    300: '#CEBEFF',
-    400: '#B69EFF',
-    500: '#9C7DFF',
-    600: '#8A5FFF',
-    700: '#7645E8',
-    800: '#6234BB',
-    900: '#502D93',
-    950: '#2D1959',
+    50: '#F0FDFA',
+    100: '#CCFBF1',
+    200: '#99F6E4',
+    300: '#5EEAD4',
+    400: '#2DD4BF',
+    500: '#14B8A6',
+    600: '#0D9488',
+    700: '#0F766E',
+    800: '#115E59',
+    900: '#134E4A',
+    950: '#042F2E',
   },
   green: {
     50: '#F0FDF4',