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/butter3/Butter3.md

@@ -1,5 +1,7 @@
 # BUTTER3: Ehlers 3-Pole Butterworth Filter
 
+> *Steeper rolloff demands a third pole.*
+
 | Property         | Value                            |
 | ---------------- | -------------------------------- |
 | **Category**     | Filter                        |
@@ -17,8 +19,6 @@
 - Requires `6 * period` bars of warmup before first valid output (IsHot = true).
 - Validated against TA-Lib, Skender, and Tulip reference implementations where available.
 
-> "Steeper rolloff demands a third pole."
-
 The 3-Pole Butterworth Filter (BUTTER3) extends the classic Butterworth design to third order, providing -60 dB/decade rolloff compared to -40 dB/decade for the 2-pole variant. Developed from John Ehlers' formulation in "Cybernetic Analysis for Stocks and Futures" (2004), this implementation uses the same pole placement as the 3-pole Super Smoother (SSF3) but with binomial (1,3,3,1) feedforward weights that preserve the maximally flat passband characteristic. The steeper rolloff makes BUTTER3 more effective at rejecting high-frequency noise, at the cost of slightly more lag than BUTTER2.
 
 ## Core Concepts