feat(dynamics): add PlusDI, MinusDI, PlusDM, MinusDM indicators

Complete thin Dx-composition wrapper indicators with full test coverage:

- PlusDi/MinusDi: Directional Indicator wrappers (DiPlus/DiMinus from Dx)
- PlusDm/MinusDm: Directional Movement wrappers (DmPlus/DmMinus from Dx)
- Individual validation tests per indicator directory (TALib, Skender, bounds)
- Combined unit tests (DiDm.Tests.cs) and validation tests (DiDm.Validation.Tests.cs)
- Quantower wrappers + tests for all 4 indicators
- PineScript v6 implementations with compensated RMA
- Normalized .md documentation for all indicators and categories
- 182 tests passing, 0 failures

lib/volume/pvo/Pvo.md

@@ -1,5 +1,7 @@
 # PVO: Percentage Volume Oscillator
 
+> *Volume precedes price—PVO measures whether the market is inhaling or exhaling.*
+
 | Property         | Value                            |
 | ---------------- | -------------------------------- |
 | **Category**     | Volume                        |
@@ -16,8 +18,6 @@
 - Requires `slowPeriod` bars of warmup before first valid output (IsHot = true).
 - Validated against TA-Lib, Skender, and Tulip reference implementations where available.
 
-> "Volume precedes price—PVO measures whether the market is inhaling or exhaling."
-
 The Percentage Volume Oscillator (PVO) measures the difference between two exponential moving averages of volume, expressed as a percentage of the slower EMA. Essentially the MACD of volume, PVO identifies whether volume is expanding (accumulation) or contracting (distribution) relative to its recent history. This percentage normalization makes it comparable across instruments with vastly different volume profiles.
 
 ## Historical Context