Fix dropdown menu and add Back to Dashboard button in profile and wallet pages

- Add visible 'Back to Dashboard' button in profile.html header
- Add visible 'Back to Dashboard' button in wallet.html header
- Add logout function to wallet.html
- Both buttons use role-based navigation (player -> player.html, broker -> broker.html)

web/profile.html

@@ -15,6 +15,7 @@
         </div>
         <div class="user-info">
             <span id="user-balance" class="balance-display">Balance: $0.00</span>
+            <a href="#" class="btn btn-secondary" id="back-to-dashboard" onclick="goToDashboard(); return false;">Back to Dashboard</a>
             <div class="nav-user">
                 <div class="user-profile" onclick="toggleUserDropdown()">
                     <img id="user-avatar" src="data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 100 100'%3E%3Ccircle cx='50' cy='50' r='50' fill='%234a5568'/%3E%3Ccircle cx='50' cy='35' r='20' fill='%23718096'/%3E%3Cellipse cx='50' cy='85' rx='35' ry='25' fill='%23718096'/%3E%3C/svg%3E" alt="Avatar" class="user-avatar">

web/wallet.html

@@ -15,6 +15,7 @@
             </div>
             <div class="user-info">
                 <span id="user-balance" class="balance-display">Balance: $0.00</span>
+                <a href="#" class="btn btn-secondary" id="back-to-dashboard" onclick="goToDashboard(); return false;">Back to Dashboard</a>
                 <div class="nav-user">
                     <div class="user-profile" onclick="toggleUserDropdown()">
                         <img id="user-avatar" src="data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 100 100'%3E%3Ccircle cx='50' cy='50' r='50' fill='%234a5568'/%3E%3Ccircle cx='50' cy='35' r='20' fill='%23718096'/%3E%3Cellipse cx='50' cy='85' rx='35' ry='25' fill='%23718096'/%3E%3C/svg%3E" alt="Avatar" class="user-avatar">
@@ -565,6 +566,15 @@
                 });
             }
         });
+
+        // Logout function
+        function logout() {
+            localStorage.removeItem('authToken');
+            localStorage.removeItem('currentUser');
+            localStorage.removeItem('refreshToken');
+            localStorage.removeItem('tokenExpiresAt');
+            window.location.href = 'index.html';
+        }
     </script>
 </body>
 </html>
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