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/channels/maenv/maenv.md

@@ -1,5 +1,7 @@
 # MAENV: Moving Average Envelope
 
+> *A fixed percentage above and below a moving average — the simplest envelope assumes symmetry in price behavior.*
+
 | Property         | Value                            |
 | ---------------- | -------------------------------- |
 | **Category**     | Channel                        |
@@ -71,25 +73,6 @@ $O(1)$ for SMA and EMA modes. $O(n)$ for WMA mode due to the weighted sum.
 | `ma_type` | Moving average type: 0=SMA, 1=EMA, 2=WMA | 1 (EMA) | $\{0, 1, 2\}$ |
 | `source` | Input price series | close | |
 
-### Pseudo-code
-
-```
-function MAENV(source, period, percentage, ma_type):
-    validate: period > 0, percentage > 0
-
-    // Compute center line based on MA type
-    if ma_type == 0: middle = SMA(source, period)
-    if ma_type == 1: middle = EMA(source, period)  // with warmup
-    if ma_type == 2: middle = WMA(source, period)
-
-    // Fixed percentage offset
-    dist = middle * percentage / 100
-    upper = middle + dist
-    lower = middle - dist
-
-    return [middle, upper, lower]
-```
-
 ### Output Interpretation
 
 | Output | Description |