Refactor: Convert indicators to self-contained files

- Created moving_average.js consolidating ma.js, ma_indicator.js, sma.js, ema.js
- Made all indicators self-contained with embedded:
  * Math logic (no external dependencies)
  * Metadata (getMetadata())
  * Signal calculation (calculateXXXSignal)
  * Base class (inline BaseIndicator)
- Updated macd.js, hts.js to inline EMA/MA calculations
- Added signal functions to RSI, BB, Stochastic, ATR indicators
- Updated indicators/index.js to export both classes and signal functions
- Simplified signals-calculator.js to orchestrate using indicator signal functions
- Removed obsolete files: ma.js, base.js, ma_indicator.js, sma.js, ema.js

All indicators now fully self-contained with no external file dependencies
for math, signal calculation, or base class.

src/api/dashboard/static/js/indicators/stoch.js

@@ -1,6 +1,74 @@
-import { BaseIndicator } from './base.js';
+// Self-contained Stochastic Oscillator indicator
+// Includes math, metadata, signal calculation, and base class
 
+// Signal constants (defined in each indicator file)
+const SIGNAL_TYPES = {
+    BUY: 'buy',
+    SELL: 'sell',
+    HOLD: 'hold'
+};
+
+const SIGNAL_COLORS = {
+    buy: '#26a69a',
+    hold: '#787b86',
+    sell: '#ef5350'
+};
+
+// Base class (inline replacement for BaseIndicator)
+class BaseIndicator {
+    constructor(config) {
+        this.id = config.id;
+        this.type = config.type;
+        this.name = config.name;
+        this.params = config.params || {};
+        this.timeframe = config.timeframe || '1m';
+        this.series = [];
+        this.visible = config.visible !== false;
+        this.cachedResults = null;
+        this.cachedMeta = null;
+        this.lastSignalTimestamp = null;
+        this.lastSignalType = null;
+    }
+}
+
+// Signal calculation for Stochastic
+function calculateStochSignal(indicator, lastCandle, prevCandle, values) {
+    const k = values?.k;
+    const d = values?.d;
+    const overbought = indicator.params?.overbought || 80;
+    const oversold = indicator.params?.oversold || 20;
+    
+    if (!k || !d) {
+        return null;
+    }
+
+    if (k < oversold && d < oversold) {
+        return {
+            type: SIGNAL_TYPES.BUY,
+            strength: Math.min(50 + (oversold - k) * 2, 100),
+            value: k,
+            reasoning: `Stochastic %K (${k.toFixed(2)}) and %D (${d.toFixed(2)}) oversold (<${oversold})`
+        };
+    } else if (k > overbought && d > overbought) {
+        return {
+            type: SIGNAL_TYPES.SELL,
+            strength: Math.min(50 + (k - overbought) * 2, 100),
+            value: k,
+            reasoning: `Stochastic %K (${k.toFixed(2)}) and %D (${d.toFixed(2)}) overbought (>${overbought})`
+        };
+    } else {
+        return null;
+    }
+}
+
+// Stochastic Oscillator Indicator class
 export class StochasticIndicator extends BaseIndicator {
+    constructor(config) {
+        super(config);
+        this.lastSignalTimestamp = null;
+        this.lastSignalType = null;
+    }
+
     calculate(candles) {
         const kPeriod = this.params.kPeriod || 14;
         const dPeriod = this.params.dPeriod || 3;
@@ -33,12 +101,28 @@ export class StochasticIndicator extends BaseIndicator {
             name: 'Stochastic',
             description: 'Stochastic Oscillator - compares close to high-low range',
             inputs: [
-                { name: 'kPeriod', label: 'K Period', type: 'number', default: 14 },
-                { name: 'dPeriod', label: 'D Period', type: 'number', default: 3 }
+                { 
+                    name: 'kPeriod', 
+                    label: '%K Period', 
+                    type: 'number', 
+                    default: 14, 
+                    min: 1, 
+                    max: 100,
+                    description: 'Lookback period for %K calculation'
+                },
+                { 
+                    name: 'dPeriod', 
+                    label: '%D Period', 
+                    type: 'number', 
+                    default: 3, 
+                    min: 1, 
+                    max: 20,
+                    description: 'Smoothing period for %D (SMA of %K)'
+                }
             ],
             plots: [
-                { id: 'k', color: '#3f51b5', title: '%K' },
-                { id: 'd', color: '#ff9800', title: '%D' }
+                { id: 'k', color: '#3f51b5', title: '%K', style: 'solid', width: 1 },
+                { id: 'd', color: '#ff9800', title: '%D', style: 'solid', width: 1 }
             ],
             displayMode: 'pane',
             paneMin: 0,
@@ -46,3 +130,5 @@ export class StochasticIndicator extends BaseIndicator {
         };
     }
 }
+
+export { calculateStochSignal };