fix: dropdown Administration et raccourcis tableau de bord admin

- Ajout de `relative` sur le conteneur du menu Administration +
  `top-full left-0` sur le dropdown (position correcte sous le bouton)
- Grille de raccourcis dans le tableau de bord admin : Utilisateurs,
  Sections, Types de sources, Types de lieux

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

resources/views/layouts/navigation.blade.php

@@ -29,7 +29,7 @@
 
                     @if(auth()->user()->isSectionManager())
                         <!-- Menu Administration -->
-                        <div class="hidden sm:flex sm:items-center" x-data="{ adminOpen: false }">
+                        <div class="relative hidden sm:flex sm:items-center" x-data="{ adminOpen: false }">
                             <button @click="adminOpen = !adminOpen"
                                     class="inline-flex items-center px-1 pt-1 border-b-2 text-sm font-medium leading-5 transition duration-150 ease-in-out
                                            {{ request()->routeIs('admin.*') ? 'border-indigo-400 text-gray-900' : 'border-transparent text-gray-500 hover:text-gray-700 hover:border-gray-300' }}">
@@ -40,7 +40,7 @@
                             </button>
 
                             <div x-show="adminOpen" @click.outside="adminOpen = false" x-cloak
-                                 class="absolute top-14 mt-1 w-56 bg-white rounded-md shadow-lg border border-gray-100 z-50">
+                                 class="absolute top-full left-0 mt-1 w-56 bg-white rounded-md shadow-lg border border-gray-100 z-50">
                                 @if(auth()->user()->isAdmin())
                                     <a href="{{ route('admin.dashboard') }}"
                                        class="block px-4 py-2 text-sm font-medium text-indigo-700 hover:bg-indigo-50 border-b border-gray-100">