[Testing] Unit tests for all TechnicalAnalysis indicators

[jackby03]

Summary

TechnicalAnalysis has no tests. Any change to an indicator formula is undetectable. The module does float arithmetic that is easy to get wrong and critical to get right.

What needs to be done

Add unit tests in tests/Omnijure.Core.Tests/ for every indicator:

Test class	Cases
SmaTests	Known sequence → expected value, period > buffer length returns 0
EmaTests	Matches reference value from TradingView for BTCUSDT 1h data
RsiTests	Wilder smoothing matches known RSI(14) reference values
MacdTests	MACD line, signal line, histogram correct
BollingerBandsTests	Upper/Lower within tolerance, squeeze detection
AtrTests	Matches reference ATR(14) values

• Use [Theory] with inline data for deterministic inputs
• Tolerance: Math.Abs(actual - expected) < 0.01f
• Add edge cases: empty buffer, buffer smaller than period, flat price sequence

Acceptance criteria

• All 6 indicator classes have passing tests
• Tests run in CI (no network access, no file I/O)
• Code coverage for TechnicalAnalysis.cs ≥ 90%
• Tests complete in < 100ms total

References

• src/Omnijure.Core/Shared/Lib/Math/TechnicalAnalysis.cs
• tests/Omnijure.Core.Tests/
• Depends on issue [Core] Expand TechnicalAnalysis: EMA, MACD, Bollinger Bands, VWAP, ATR, Stochastic + stateful RSI #4 (EMA, MACD, Bollinger, ATR must exist first)