Fix sidebar dropdown direction and accidental mobile drawer opening

- CSS: When sidebar is collapsed, open user-menu dropdown to the right
  (left: 0, right: auto) via data-sidebar-expanded="false" selector.
- JS: Guard drawerToggle change handler – prevent mobile drawer from
  opening on desktop viewports (window.innerWidth >= 1024).
- HTML: Add phx-update="ignore" to mobile-drawer checkbox to prevent
  LiveView from resetting its checked state on DOM patches.

lib/mv_web/components/layouts.ex

@@ -54,7 +54,7 @@ defmodule MvWeb.Layouts do
         data-sidebar-expanded="true"
         phx-hook="SidebarState"
       >
-        <input id="mobile-drawer" type="checkbox" class="drawer-toggle" />
+        <input id="mobile-drawer" type="checkbox" class="drawer-toggle" phx-update="ignore" />
 
         <div class="drawer-content flex flex-col relative z-0">
           <!-- Mobile Header (only visible on mobile) -->