[Core] Expand TechnicalAnalysis: EMA, MACD, Bollinger Bands, VWAP, ATR, Stochastic + stateful RSI

[jackby03]

Summary

TechnicalAnalysis currently has SMA and a stateless RSI. A real trading platform needs a broader set of indicators, and RSI must use Wilder's smoothing (stateful) to match values produced by TradingView and most exchanges.

Indicators to add

Indicator	Notes
EMA	Exponential Moving Average
MACD	EMA(12) - EMA(26) + Signal EMA(9)
Bollinger Bands	SMA ± 2σ, return Upper/Mid/Lower
VWAP	Cumulative since session open
ATR	Average True Range (Wilder's)
Stochastic	%K and %D

Stateful RSI fix

• Current implementation recalculates full window every tick — O(n) each frame
• Replace with Wilder's smoothing: AvgGain = (PrevAvgGain × 13 + Gain) / 14
• Add a RsiState struct to carry state across ticks

Acceptance criteria

• All 6 indicators listed above are implemented
• RSI uses Wilder's smoothing and matches reference values within 0.01
• Each indicator has a dedicated unit test with known input → expected output
• No heap allocation in the hot path (use Span<float> where possible)

References

• src/Omnijure.Core/Shared/Lib/Math/TechnicalAnalysis.cs
• src/Omnijure.Core/Shared/Lib/Math/SimdOps.cs