Fix historical backtests tab not showing data

Root cause: switchTab() didn't show the historical panel (pnl-historical).
Added panel visibility toggle and tab highlight for 'historical' tab.

Also fixed broken JS quote escaping in loadHistBT function — ''+s+''
was missing backslash-escaped quotes, causing "Unexpected string" syntax
error that prevented the entire script from executing.

Historical tab now shows 7 real-data backtest cards from Hyperliquid
mainnet candles.

dashboard/static/index.html

@@ -214,10 +214,11 @@ function initDetChart(){
 // ═══════════ Tab switching ═══════════
 function switchTab(t){
   currentTab=t;
-  ['live','paper','backtest'].forEach(function(x){document.getElementById('tl-'+x).className=t===x?'tab on':'tab'});
+  ['live','paper','backtest','historical'].forEach(function(x){document.getElementById('tl-'+x).className=t===x?'tab on':'tab'});
   document.getElementById('pnl-live').className=t==='live'?'panel show':'panel';
   document.getElementById('pnl-paper').className=t==='paper'?'panel show':'panel';
   document.getElementById('pnl-backtest').className=t==='backtest'?'panel show':'panel';
+  document.getElementById('pnl-historical').className=t==='historical'?'panel show':'panel';
   if(t==='live'&&lastData)renLive(lastData);
   if(t==='paper'&&lastPaper)renPaper(lastPaper);
   if(t==='backtest')loadBT();
@@ -402,6 +403,35 @@ function loadBT(){
   })
 }
 
+// ═══════════ Historical backtests ═══════════
+var lastHist={};
+function loadHistBT(){
+  fetch('/cv/api/backtests/historical').then(function(r){return r.json()}).then(function(data){
+    lastHist={};
+    for(var i=0;i<data.length;i++){var b=data[i];if(!lastHist[b.strategy])lastHist[b.strategy]=b;}
+    var h='';
+    for(var s in lastHist){var b=lastHist[s];var pnl=b.pnl_pct||0;
+      h+='<div class="scard" onclick="openHistDetail(\'+s+\')"><div class="sh"><div><div class="sname">'+s+'</div><div class="salloc">30d '+b.coin+' &middot; Mainnet</div></div><span class="stag run">REAL DATA</span></div><div class="spnl '+(pnl>=0?'up':'dn')+'">'+(pnl>=0?'+':'')+pnl.toFixed(2)+'%</div><div class="smeta"><span>Sharpe: <b>'+b.sharpe.toFixed(2)+'</b></span><span>DD: <b class="red">'+(b.max_dd*100).toFixed(2)+'%</b></span><span>Win: <b>'+Math.round(b.win_rate*100)+'%</b></span></div></div>';
+    }
+    document.getElementById('hist-sgrid').innerHTML=h||'<div style="padding:20px;color:var(--tx)">No historical backtests. Run: python backtests/historical_runner.py --coin BTC --strategy all</div>';
+  })
+}
+function openHistDetail(strat){
+  var b=lastHist[strat];if(!b)return;
+  document.getElementById('detail-overlay').classList.add('on');
+  document.getElementById('fee-toggle-wrap').style.display='inline';
+  document.getElementById('fee-tier-sel').style.display='inline';
+  document.getElementById('stake-tier-sel').style.display='inline';
+  document.getElementById('dl-csv').style.display='none';
+  document.getElementById('fee-toggle').checked=true; feeOn=true; currentBTName=b.name;
+  document.getElementById('det-name').textContent=strat+' (Historical '+b.coin+')';
+  fetch('/cv/api/backtest/historical/'+encodeURIComponent(b.name)).then(function(r){return r.json()}).then(function(full){
+    lastBTFull=full; renderBTDetail(full);
+  }).catch(function(e){
+    document.getElementById('det-trades').innerHTML='<tr><td colspan="7" style="text-align:center;color:var(--rd);padding:20px">Failed: '+e.message+'</td></tr>';
+  });
+}
+
 // ═══════════ Init ═══════════
 initDetChart();connect();loadBT();
 // ═══════════ Risk Analytics ═══════════