feat: top 20 clientes por volume com cards clicaveis agrupados por faixa

- fetchClientList agora retorna volume USD, ops, meses ativos e ultima op
- Top 20 clientes exibidos como cards clicaveis na tela inicial
- Agrupados em 3 faixas: Alto Volume, Medio Volume, Menor Volume
- Cards mostram volume total, ops e media mensal
- Click no card carrega o dashboard 360 do cliente

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

src/admin-cliente.js

@@ -130,10 +130,36 @@ function buildAdminClienteHTML(user) {
   .client-selected-badge .badge-clear:hover { border-color: var(--red); color: var(--red); }
 
   /* Empty State */
-  .empty-state { text-align: center; padding: 80px 20px; color: var(--text-muted); }
-  .empty-state .empty-icon { font-size: 64px; margin-bottom: 16px; opacity: 0.3; }
-  .empty-state h2 { font-size: 20px; font-weight: 700; margin-bottom: 8px; color: var(--text-secondary); }
-  .empty-state p { font-size: 14px; }
+  .empty-state { text-align: center; padding: 40px 20px 20px; color: var(--text-muted); }
+  .empty-state .empty-icon { font-size: 48px; margin-bottom: 12px; opacity: 0.3; }
+  .empty-state h2 { font-size: 20px; font-weight: 700; margin-bottom: 6px; color: var(--text-secondary); }
+  .empty-state p { font-size: 14px; margin-bottom: 0; }
+
+  /* Top Clients Grid */
+  .top-clients-section { max-width: 1200px; margin: 0 auto; padding: 0 16px; }
+  .top-clients-tier { margin-bottom: 20px; }
+  .tier-header { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; padding: 0 4px; }
+  .tier-dot { width: 10px; height: 10px; border-radius: 50%; flex-shrink: 0; }
+  .tier-dot.tier-high { background: var(--green, #1E8E3E); }
+  .tier-dot.tier-mid { background: var(--blue, #58A6FF); }
+  .tier-dot.tier-low { background: var(--orange, #F0883E); }
+  .tier-label { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 1px; color: var(--text-muted); }
+  .tier-count { font-size: 11px; color: var(--text-muted); margin-left: auto; }
+  .top-clients-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 10px; }
+  .top-client-card {
+    padding: 14px 16px; border-radius: 10px; cursor: pointer; transition: all 0.15s;
+    background: var(--card); border: 1px solid var(--border); position: relative; overflow: hidden;
+  }
+  .top-client-card:hover { border-color: var(--tc-accent); transform: translateY(-1px); box-shadow: 0 4px 12px rgba(0,0,0,0.1); }
+  [data-theme="dark"] .top-client-card { background: rgba(255,255,255,0.02); }
+  [data-theme="dark"] .top-client-card:hover { background: rgba(0,255,136,0.04); border-color: #00FF88; box-shadow: 0 4px 16px rgba(0,255,136,0.08); }
+  .top-client-card .tc-rank { position: absolute; top: 8px; right: 10px; font-size: 10px; font-weight: 800; color: var(--text-muted); opacity: 0.5; }
+  .top-client-card .tc-name { font-size: 13px; font-weight: 700; color: var(--text); margin-bottom: 6px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; padding-right: 24px; }
+  .top-client-card .tc-stats { display: flex; gap: 12px; font-size: 11px; color: var(--text-secondary); }
+  .top-client-card .tc-stats span { display: flex; align-items: center; gap: 3px; }
+  .top-client-card .tc-vol { font-weight: 700; color: var(--tc-accent); }
+  [data-theme="dark"] .top-client-card .tc-name { font-family: 'SF Mono','Fira Code','Consolas',monospace; }
+  @media (max-width: 480px) { .top-clients-grid { grid-template-columns: 1fr 1fr; gap: 8px; } .top-client-card { padding: 10px 12px; } }
 
   /* === Profile Card === */
   .profile-card { border-radius: 16px; padding: 24px; margin-bottom: 24px; display: flex; align-items: center; gap: 24px; flex-wrap: wrap; }
@@ -329,11 +355,14 @@ ${buildHeader({ role: role, userName: user.nome, activePage: 'cliente' })}
     <button class="badge-clear" onclick="clearClient()">Limpar</button>
   </div>
 
-  <!-- Empty State -->
-  <div class="empty-state" id="emptyState">
-    <div class="empty-icon">&#x1F50D;</div>
-    <h2>Selecione um cliente</h2>
-    <p>Use a busca acima para encontrar um cliente e visualizar sua analise 360 completa.</p>
+  <!-- Empty State + Top Clients -->
+  <div id="emptyState">
+    <div class="empty-state">
+      <div class="empty-icon">&#x1F50D;</div>
+      <h2>Selecione um cliente</h2>
+      <p>Busque acima ou clique em um dos top clientes abaixo</p>
+    </div>
+    <div class="top-clients-section" id="topClientsSection"></div>
   </div>
 
   <!-- Content Area -->
@@ -725,14 +754,45 @@ function renderNetting(data) {
 
 // === Client Search ===
 var _searchTimer = null;
+function fmtVolShort(v) {
+  if (v >= 1e6) return '$' + (v/1e6).toFixed(1) + 'M';
+  if (v >= 1e3) return '$' + (v/1e3).toFixed(0) + 'K';
+  return '$' + v;
+}
 function loadClients() {
   fetch('/admin/api/clientes').then(function(r){return r.json();}).then(function(data) {
     clientList = data;
+    renderTopClients(data.slice(0, 20));
     var params = new URLSearchParams(window.location.search);
     var deepId = params.get('id');
     if (deepId) { var m = clientList.find(function(c){return String(c.id)===String(deepId);}); if (m) selectClient(m.id, m.nome); }
   }).catch(function(e){ console.error('loadClients:', e); });
 }
+function renderTopClients(top) {
+  var el = document.getElementById('topClientsSection');
+  if (!el || !top.length) return;
+  // Group by volume tier
+  var high = [], mid = [], low = [];
+  top.forEach(function(c, i) { c._rank = i + 1; });
+  var maxVol = top[0] ? top[0].vol : 1;
+  top.forEach(function(c) {
+    var ratio = c.vol / maxVol;
+    if (ratio >= 0.3) high.push(c);
+    else if (ratio >= 0.05) mid.push(c);
+    else low.push(c);
+  });
+  function buildCards(list) {
+    return '<div class="top-clients-grid">' + list.map(function(c) {
+      var avgMonth = c.months > 0 ? c.vol / c.months : c.vol;
+      return '<div class="top-client-card" onclick="selectClient(\\''+c.id+'\\',\\''+c.nome.replace(/'/g,"\\\\'")+'\\')"><span class="tc-rank">#'+c._rank+'</span><div class="tc-name" title="'+c.nome.replace(/"/g,'&quot;')+'">'+c.nome+'</div><div class="tc-stats"><span class="tc-vol">'+fmtVolShort(c.vol)+'</span><span>'+c.ops+' ops</span><span>~'+fmtVolShort(Math.round(avgMonth))+'/m</span></div></div>';
+    }).join('') + '</div>';
+  }
+  var html = '';
+  if (high.length) html += '<div class="top-clients-tier"><div class="tier-header"><span class="tier-dot tier-high"></span><span class="tier-label">Alto Volume</span><span class="tier-count">'+high.length+' clientes</span></div>'+buildCards(high)+'</div>';
+  if (mid.length) html += '<div class="top-clients-tier"><div class="tier-header"><span class="tier-dot tier-mid"></span><span class="tier-label">Medio Volume</span><span class="tier-count">'+mid.length+' clientes</span></div>'+buildCards(mid)+'</div>';
+  if (low.length) html += '<div class="top-clients-tier"><div class="tier-header"><span class="tier-dot tier-low"></span><span class="tier-label">Menor Volume</span><span class="tier-count">'+low.length+' clientes</span></div>'+buildCards(low)+'</div>';
+  el.innerHTML = html;
+}
 document.getElementById('searchInput').addEventListener('input', function(e) {
   clearTimeout(_searchTimer);
   var val = e.target.value.trim().toLowerCase();