Fix active state logic for sidebar menu items

[hcancelik]

This pull request fixes the way active navigation items are determined in the NavMain.vue component. The main change is the introduction of a new isActive helper function, which handles both string and object types for the href property.

Navigation logic improvement:

• Added an isActive function to correctly determine if a navigation item is active by handling both string and object href types, and updated the SidebarMenuButton to use this function for its is-active prop.

[joetannenbaum]

Thanks!