feat: collapsible groups in IP addressing view

Groups are collapsed by default. Click a header to toggle it; chevron
rotates to indicate state. "Expand all" / "Collapse all" buttons in the
page header; each is disabled when the action is already complete.

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

frontend/src/components/IpAddressing.vue

@@ -10,6 +10,10 @@
 
     <div class="page-header">
       <h1>{{ t('ipAddressing') }}</h1>
+      <div v-if="!allHaveNoIp" class="header-actions">
+        <button class="btn-toggle-all" @click="expandAll"   :disabled="allExpanded">{{ t('expandAll') }}</button>
+        <button class="btn-toggle-all" @click="collapseAll" :disabled="allCollapsed">{{ t('collapseAll') }}</button>
+      </div>
     </div>
 
     <div v-if="allHaveNoIp" class="empty">
@@ -18,7 +22,10 @@
 
     <div v-else class="groups">
       <div v-for="group in groups" :key="group.key" class="group">
-        <div class="group-header" :style="{ borderLeftColor: group.color }">
+        <div class="group-header" :style="{ borderLeftColor: group.color }" @click="toggleGroup(group.key)">
+          <svg class="chevron" :class="{ open: expanded.has(group.key) }" width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round">
+            <polyline points="9 18 15 12 9 6"/>
+          </svg>
           <span class="badge-vlan" :style="{ background: group.color }">
             {{ group.badge }}
           </span>
@@ -27,7 +34,7 @@
           <span class="group-count">{{ group.rows.length }}</span>
         </div>
 
-        <div class="table-wrap">
+        <div v-show="expanded.has(group.key)" class="table-wrap">
           <table>
             <thead>
               <tr>
@@ -65,7 +72,7 @@
 </template>
 
 <script setup>
-import { ref, computed } from 'vue'
+import { ref, computed, watch } from 'vue'
 import { t } from '../i18n.js'
 import { detectOs } from '../brandIcons.js'
 import DeviceFormModal from './DeviceFormModal.vue'
@@ -77,6 +84,24 @@ const props = defineProps({
 const emit = defineEmits(['refresh'])
 
 const editingDevice = ref(null)
+const expanded = ref(new Set())
+
+function toggleGroup(key) {
+  const s = new Set(expanded.value)
+  s.has(key) ? s.delete(key) : s.add(key)
+  expanded.value = s
+}
+
+function expandAll() {
+  expanded.value = new Set(groups.value.map(g => g.key))
+}
+
+function collapseAll() {
+  expanded.value = new Set()
+}
+
+const allExpanded  = computed(() => groups.value.length > 0 && groups.value.every(g => expanded.value.has(g.key)))
+const allCollapsed = computed(() => groups.value.every(g => !expanded.value.has(g.key)))
 
 function ipToNum(ip) {
   if (!ip) return 0
@@ -162,6 +187,7 @@ const allHaveNoIp = computed(() => groups.value.length === 0)
 .page-header {
   display: flex;
   align-items: center;
+  gap: 12px;
   margin-bottom: 20px;
 }
 
@@ -171,6 +197,32 @@ const allHaveNoIp = computed(() => groups.value.length === 0)
   color: var(--text-primary);
 }
 
+.header-actions {
+  margin-left: auto;
+  display: flex;
+  gap: 6px;
+}
+
+.btn-toggle-all {
+  padding: 4px 12px;
+  font-size: 12px;
+  font-weight: 500;
+  border: 1.5px solid var(--border);
+  border-radius: 6px;
+  background: var(--bg-chip);
+  color: var(--text-secondary);
+  cursor: pointer;
+  transition: background 0.15s, color 0.15s;
+}
+.btn-toggle-all:hover:not(:disabled) {
+  background: var(--border);
+  color: var(--text-primary);
+}
+.btn-toggle-all:disabled {
+  opacity: 0.35;
+  cursor: default;
+}
+
 .empty {
   color: var(--text-muted);
   font-size: 14px;
@@ -200,6 +252,20 @@ const allHaveNoIp = computed(() => groups.value.length === 0)
   border-bottom: 1px solid var(--border);
   border-left: 4px solid transparent;
   background: var(--bg-thead);
+  cursor: pointer;
+  user-select: none;
+}
+.group-header:hover {
+  background: var(--bg-card-hover);
+}
+
+.chevron {
+  color: var(--text-muted);
+  flex-shrink: 0;
+  transition: transform 0.18s ease;
+}
+.chevron.open {
+  transform: rotate(90deg);
 }
 
 .badge-vlan {

frontend/src/i18n.js

@@ -19,6 +19,8 @@ const LANGS = {
     colOs: 'OS',
     fieldOs: "Système d'exploitation",
     noIpConfigured: 'Aucune adresse IP configurée.',
+    expandAll: 'Tout déplier',
+    collapseAll: 'Tout replier',
     discovery: '🔍 Découverte auto',
     statsNetwork: 'Réseau',
     statsNetworks: 'Réseaux',
@@ -199,6 +201,8 @@ const LANGS = {
     colOs: 'OS',
     fieldOs: 'Operating system',
     noIpConfigured: 'No IP address configured.',
+    expandAll: 'Expand all',
+    collapseAll: 'Collapse all',
     discovery: '🔍 Auto discovery',
     statsNetwork: 'Network',
     statsNetworks: 'Networks',
@@ -373,6 +377,8 @@ const LANGS = {
     colOs: 'SO',
     fieldOs: 'Sistema operativo',
     noIpConfigured: 'No hay ninguna dirección IP configurada.',
+    expandAll: 'Expandir todo',
+    collapseAll: 'Contraer todo',
     discovery: '🔍 Descubrimiento auto',
     statsNetwork: 'Red',
     statsNetworks: 'Redes',