feat: suppression agent, RAM en Go, métriques par défaut (cpu/mem/disk/smart)

- API DELETE /api/agents/{id} — supprime agent + métriques + config + icône
- Bouton poubelle sur chaque tuile + dialog de confirmation
- RAM : affichage "utilisé/total" en Go (ex: 6.2Go/8.0Go) au lieu du %
- Config agent par défaut : cpu, memory, disk, smart activés (UDP)
- DefaultAgentConfig() dans models pour les nouveaux agents

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

dashboard/js/api.js

@@ -27,6 +27,11 @@ const API = (() => {
         if (!r.ok) throw new Error(`PUT ${path}: ${r.status}`);
     }
 
+    async function del(path) {
+        const r = await fetch(BASE + path, { method: 'DELETE' });
+        if (!r.ok) throw new Error(`DELETE ${path}: ${r.status}`);
+    }
+
     async function postForm(path, formData) {
         const r = await fetch(BASE + path, { method: 'POST', body: formData });
         if (!r.ok) throw new Error(`POST ${path}: ${r.status}`);
@@ -44,6 +49,7 @@ const API = (() => {
             fd.append('icon', file);
             return postForm(`/api/agents/${id}/icon`, fd);
         },
+        deleteAgent:      (id) => del(`/api/agents/${id}`),
         iconUrl:          (id) => `/api/agents/${id}/icon`,
     };
 })();

dashboard/js/grid.js

@@ -81,7 +81,7 @@ const Grid = (() => {
               <div class="g-ico" data-tip="RAM"><i class="fa-solid fa-memory"></i></div>
               <div class="g-bar"><div class="g-fill ${offline ? '' : gFill(memPct ?? 0)}"
                 style="width:${offline ? 0 : (memPct ?? 0).toFixed(0)}%"></div></div>
-              <span class="g-val">${offline ? '—' : fmtPct(memPct)}</span>
+              <span class="g-val">${offline ? '—' : (metrics?.memory_used && metrics?.memory_total ? fmt(metrics.memory_used) + '/' + fmt(metrics.memory_total) : '—')}</span>
             </div>
             <div class="g-row">
               <div class="g-ico" data-tip="Disque"><i class="fa-solid fa-hard-drive"></i></div>
@@ -94,6 +94,10 @@ const Grid = (() => {
             ${offline
                 ? '<i class="fa-solid fa-circle-xmark" style="color:var(--err)"></i><span style="color:var(--err)">Hors ligne</span>'
                 : `<i class="fa-solid fa-clock"></i><span>${uptimeStr}</span>`}
+            <button class="btn-del-agent" title="Supprimer cet agent"
+              onclick="event.stopPropagation();Popups.confirmDeleteAgent('${esc(id)}','${esc(agent.hostname)}')">
+              <i class="fa-solid fa-trash"></i>
+            </button>
           </div>
         </div>`;
     }
@@ -139,6 +143,13 @@ const Grid = (() => {
         document.getElementById('stat-err').textContent = err;
     }
 
+    function removeAgent(id) {
+        _agents.delete(id);
+        const el = document.getElementById('tile-' + id);
+        if (el) el.remove();
+        updateStats();
+    }
+
     function getAgent(id) { return _agents.get(id); }
 
     function updateStatus(agentId, status) {
@@ -150,5 +161,5 @@ const Grid = (() => {
         updateStats();
     }
 
-    return { refresh, update, updateStatus, getAgent, fmt, fmtPct };
+    return { refresh, update, updateStatus, removeAgent, getAgent, fmt, fmtPct };
 })();

dashboard/js/popups.js

@@ -406,10 +406,32 @@ const Popups = (() => {
         document.getElementById('overlay-smart').style.display = 'flex';
     }
 
+    // ══ SUPPRESSION AGENT ══
+    let _delAgentId = null;
+
+    function confirmDeleteAgent(id, hostname) {
+        _delAgentId = id;
+        document.getElementById('del-agent-name').textContent = hostname || id;
+        document.getElementById('overlay-del').style.display = 'flex';
+    }
+
+    async function doDeleteAgent() {
+        if (!_delAgentId) return;
+        const id = _delAgentId;
+        document.getElementById('overlay-del').style.display = 'none';
+        _delAgentId = null;
+        try {
+            await API.deleteAgent(id);
+            Grid.removeAgent(id);
+        } catch (e) {
+            alert('Erreur lors de la suppression : ' + e.message);
+        }
+    }
+
     return {
         showDetail, hideDetail,
         showAgentCfg, sendAgentConfig, toggleCbox,
-        showSrvCfg, hideSrvCfg, saveSrvCfg,
+        showSrvCfg, hideSrvCfg, saveSrvCfg, confirmDeleteAgent, doDeleteAgent,
         showSmart,
     };
 })();