Implement Strategy tab with Ping-Pong backtesting and crossover-based signal logic

- Add 'Strategy' tab to sidebar for backtesting simulations
- Create strategy-panel.js for Ping-Pong and Accumulation mode simulations
- Refactor all indicators (MA, HTS, RSI, MACD, BB, STOCH, Hurst) to use strict crossover-based signal calculation
- Update chart.js with setSimulationMarkers and clearSimulationMarkers support
- Implement single-entry rule in Ping-Pong simulation mode

src/api/dashboard/static/js/ui/chart.js

@@ -21,9 +21,20 @@ constructor() {
         this.indicatorSignals = [];
         this.summarySignal = null;
         this.lastCandleTimestamp = null;
+        this.simulationMarkers = [];
         
         this.init();
     }
+
+    setSimulationMarkers(markers) {
+        this.simulationMarkers = markers || [];
+        this.updateSignalMarkers();
+    }
+
+    clearSimulationMarkers() {
+        this.simulationMarkers = [];
+        this.updateSignalMarkers();
+    }
     
     init() {
         this.createTimeframeButtons();
@@ -584,11 +595,18 @@ async loadSignals() {
         }
     }
     
-updateSignalMarkers() {
+    updateSignalMarkers() {
         const candles = this.allData.get(this.currentInterval);
         if (!candles || candles.length === 0) return;
         
-        const markers = calculateSignalMarkers(candles);
+        let markers = calculateSignalMarkers(candles);
+        
+        // Merge simulation markers if present
+        if (this.simulationMarkers && this.simulationMarkers.length > 0) {
+            markers = [...markers, ...this.simulationMarkers];
+            // Re-sort combined markers by time
+            markers.sort((a, b) => a.time - b.time);
+        }
         
         // If we have a marker controller, update markers through it
         if (this.markerController) {