feat: add logo asset and remove redundant defaultSource props from dashboard and auth screens

src/pages/AuthLogin.tsx

@@ -46,7 +46,6 @@ export default function AuthLogin() {
             source={require('../../assets/logo.png')} 
             style={styles.logoImage} 
             resizeMode="contain"
-            defaultSource={require('../../assets/icon.png')}
           />
         </View>
 

src/pages/AuthRegister.tsx

@@ -58,7 +58,6 @@ export default function AuthRegister() {
             source={require('../../assets/logo.png')} 
             style={styles.logoImage} 
             resizeMode="contain"
-            defaultSource={require('../../assets/icon.png')}
           />
         </View>
 

src/pages/Dashboard.tsx

@@ -159,7 +159,6 @@ export default function Dashboard() {
           source={require('../../assets/logo.png')} 
           style={styles.headerLogo} 
           resizeMode="contain"
-          defaultSource={require('../../assets/icon.png')}
         />
         <TouchableOpacity style={styles.brandPill} onPress={() => navigation.navigate('BarberProfileTab' as never)}>
           <Text style={styles.brandText}>{user?.name.charAt(0)}</Text>