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/filters/spbf/Spbf.md

@@ -1,5 +1,7 @@
 # SPBF: Ehlers Super Passband Filter
 
+> *Two EMAs walk into a frequency domain. The difference between them is the only thing worth trading.*
+
 | Property         | Value                            |
 | ---------------- | -------------------------------- |
 | **Category**     | Filter                        |
@@ -16,8 +18,6 @@
 - Requires `max(longPeriod, rmsPeriod)` bars of warmup before first valid output (IsHot = true).
 - Validated against TA-Lib, Skender, and Tulip reference implementations where available.
 
-> "Two EMAs walk into a frequency domain. The difference between them is the only thing worth trading."
-
 The **Super Passband Filter** is John Ehlers' wide-band bandpass constructed by differencing two z-transformed EMAs with Ehlers-style smoothing ($\alpha = 5/N$). It rejects both DC trend and high-frequency noise, passing only the cyclic energy between two EMA-defined cutoff frequencies. The output oscillates around zero, with an RMS trigger envelope providing signal/noise discrimination.
 
 ## Historical Context