feat(sites) : API CRUD + rattachement User<->Site + admin (ticket 2/4)

Exposition de Site via API Platform (5 operations RBAC sites.view/sites.manage),
relation User.sites (M2M user_site EAGER) + User.currentSite (M2O nullable,
ON DELETE SET NULL). Endpoint PATCH /api/me/current-site via ressource
virtuelle + processor (SiteNotAuthorizedException → 403). UserRbacProcessor
etendu avec gardes post-persist : auto-reset si currentSite retire, auto-select
premier site si null + sites non vide.

Page /admin/sites (DataTable + drawer creation/edition + modale suppression).
UserRbacDrawer etendu avec section "Sites autorises". Colonne "Sites" ajoutee
dans la table /admin/users (liste des noms separes par virgule). Sidebar
entree Sites (module: sites, permission: sites.view).

Refactor adresse : split full_address en street + complement (nullable) + getter
computed Site::getFullAddress() multi-lignes. Migration ALTER dediee pour
compat devs ayant deja joue le ticket 1. Fixtures avec vraies adresses
(Chatellerault/Fontenet/Pommevic).

Doctrine : inversedBy synchrone User.sites <-> Site.users pour maintenir la
collection inverse en memoire. User::switchCurrentSite() porte la garde
domaine (throw SiteNotAuthorizedException), aligne sur Role::ensureDeletable.
Helper skipIfSitesModuleDisabled centralise dans AbstractApiTestCase.

Tests : 182/182 (182/182 aussi module desactive, 2 skipped). 29 nouveaux tests
PHPUnit (CRUD API, switch currentSite, cascade DB, /api/me enrichi, extension
/rbac, gardes structurelles fullAddress/currentSite ignores, anti-cycle
Site.users). 11 tests Vitest sur la validation hex couleur.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/modules/sites/components/SiteDeleteModal.vue

@@ -0,0 +1,76 @@
+<template>
+    <Teleport to="body">
+        <Transition name="fade">
+            <div
+                v-if="modelValue"
+                class="fixed inset-0 z-50 flex items-center justify-center bg-black/50"
+                @click.self="cancel"
+            >
+                <div class="w-full max-w-md rounded-lg bg-white p-6 shadow-xl">
+                    <h3 class="text-lg font-semibold text-neutral-900">
+                        {{ t('admin.sites.delete.title') }}
+                    </h3>
+                    <p class="mt-3 text-sm text-neutral-600">
+                        {{ t('admin.sites.delete.message', { name: siteName }) }}
+                    </p>
+                    <div class="mt-6 flex justify-end gap-3">
+                        <MalioButton
+                            :label="t('common.cancel')"
+                            variant="secondary"
+                            @click="cancel"
+                        />
+                        <MalioButton
+                            :label="t('common.delete')"
+                            variant="danger"
+                            icon-name="mdi:delete-outline"
+                            icon-position="left"
+                            :disabled="loading"
+                            @click="confirm"
+                        />
+                    </div>
+                </div>
+            </div>
+        </Transition>
+    </Teleport>
+</template>
+
+<script setup lang="ts">
+const { t } = useI18n()
+
+defineProps<{
+    modelValue: boolean
+    siteName: string
+    loading: boolean
+}>()
+
+const emit = defineEmits<{
+    'update:modelValue': [value: boolean]
+    confirm: []
+}>()
+
+function cancel() {
+    emit('update:modelValue', false)
+}
+
+function confirm() {
+    emit('confirm')
+}
+
+function onKeydown(e: KeyboardEvent) {
+    if (e.key === 'Escape') cancel()
+}
+
+onMounted(() => document.addEventListener('keydown', onKeydown))
+onUnmounted(() => document.removeEventListener('keydown', onKeydown))
+</script>
+
+<style scoped>
+.fade-enter-active,
+.fade-leave-active {
+    transition: opacity 0.2s ease;
+}
+.fade-enter-from,
+.fade-leave-to {
+    opacity: 0;
+}
+</style>