feat: add new indicators (Decay, Edecay, MinusDi, MinusDm, PlusDi, PlusDm, Maxindex, Minindex, Sarext) and update pine scripts, core libs, validation tests, and python bindings

lib/dynamics/plusdi/PlusDi.md

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+# PLUS_DI: Plus Directional Indicator
+
+### TL;DR
+Measures upward directional movement strength as a percentage (0-100).
+
+## Introduction
+The Plus Directional Indicator (+DI) measures the strength of upward price movement relative to the true range. It is one of the components of the Directional Movement System developed by J. Welles Wilder Jr.
+
+When +DI is rising, upward price pressure is increasing. When +DI crosses above -DI, it signals a potential bullish trend. The +DI line is commonly plotted alongside -DI to visualize directional balance.
+
+## Calculation
++DI = Smoothed(+DM) / Smoothed(TR) × 100
+
+Where:
+- +DM (Plus Directional Movement) = max(High - PrevHigh, 0) when High - PrevHigh > PrevLow - Low, else 0
+- TR (True Range) = max(High - Low, |High - PrevClose|, |Low - PrevClose|)
+- Smoothing uses Wilder's method: Smooth = Smooth - Smooth/N + Input
+
+## Parameters
+| Parameter | Default | Range | Description |
+| :--- | :--- | :--- | :--- |
+| Period | 14 | 2-∞ | Wilder smoothing period |
+
+## Interpretation
+- **Rising +DI:** Strengthening upward movement
+- **+DI > -DI:** Bulls dominate; potential uptrend
+- **+DI crossover above -DI:** Bullish signal
+- **High +DI (>40):** Strong upward momentum
+
+## References
+- Wilder, J. Welles Jr. "New Concepts in Technical Trading Systems" (1978)