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/accbands/accbands.md

@@ -1,5 +1,7 @@
 # ACCBANDS: Acceleration Bands
 
+> *Acceleration bands widen with high-low range, framing the expected reach of each bar's ambition.*
+
 | Property         | Value                            |
 | ---------------- | -------------------------------- |
 | **Category**     | Channel                        |
@@ -63,26 +65,6 @@ Three independent circular buffers maintain running sums for $O(1)$ streaming up
 | `period` | Lookback period for the three SMAs ($n$) | 20 | $> 0$ |
 | `factor` | Multiplier for normalized width ($F$) | 4.0 | $> 0$ |
 
-### Pseudo-code
-
-```
-function ACCBANDS(high, low, close, period, factor):
-    // Per-bar normalized width
-    denom = high + low
-    w = denom ≠ 0 ? (high - low) / denom : 0
-
-    // Adjusted prices
-    adj_high = high * (1 + factor * w)
-    adj_low  = low  * (1 - factor * w)
-
-    // Three independent SMAs
-    upper  = SMA(adj_high, period)
-    lower  = SMA(adj_low, period)
-    middle = SMA(close, period)
-
-    return [middle, upper, lower]
-```
-
 ### Breakout Rule (Headley)
 
 A trend is confirmed when: