feat: add burger button for camp menu on the mobile

Affected URL: https://ywinnipeg.ca/camp-stephens and all subpages

Description: On mobile devices, the Camp menu does not render correctly. Some menu items are cut off or pushed outside the visible area, making them inaccessible to users.

Steps to Reproduce:

• Open the Camp Stephens page on a mobile device or use a mobile emulator.
• Scroll to the navigation area below the main header image.
• Observe that menu items such as "Register" are partially or fully cut off.

Expected Behavior: All menu items should display properly and be accessible within the screen bounds on mobile devices.

Before:

After: