Refactor indicators to include "Ehlers" in names and descriptions for clarity

- Updated the name and description of the Hilbert Trendline (HTIT) to "Ehlers Hilbert Transform Instantaneous Trend (HTIT)".
- Changed the name and description of the MESA Adaptive Moving Average (MAMA) to "Ehlers MESA Adaptive Moving Average".
- Modified the Center of Gravity (CG) indicator to "Ehlers Center of Gravity (CG)".
- Renamed the Detrended Synthetic Price (DSP) to "Ehlers Detrended Synthetic Price (DSP)".
- Updated the Autocorrelation Periodogram (EACP) to "Ehlers Autocorrelation Periodogram (EACP)".
- Changed the Homodyne Discriminator (HOMOD) to "Ehlers Homodyne Discriminator (HOMOD)".
- Updated the Hilbert Transform Dominant Cycle Period and Phase indicators to include "Ehlers" in their names.
- Renamed the Hilbert Transform Phasor Components to "Ehlers Hilbert Transform Phasor Components (HT_PHASOR)".
- Updated the SineWave indicator to "Ehlers Hilbert Transform SineWave (HT_SINE)".
- Changed the Phasor Analysis indicator to "Ehlers Hilbert Transform Phasor Components (HT_PHASOR)".
- Updated the SSF-Based Detrended Synthetic Price to "Ehlers SSF Detrended Synthetic Price (SSFDSP)".
- Renamed the Ultimate Channel to "Ehlers Ultimate Channel (UCHANNEL)".
- Added new indicators: Moving Average Variable Period (MAVP), Ehlers Predictive Moving Average (PMA), Ehlers Reverse EMA (REVERSEEMA), and Ehlers Trendflex Indicator (TRENDFLEX).
- Updated various SVG badges to reflect changes in classes, comments, source files, lines of code, methods, and public types.

lib/oscillators/deco/Deco.md

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+# DECO: Ehlers Decycler Oscillator
+
+## Overview
+
+The Decycler Oscillator (DECO) is a DSP-based oscillator developed by John F. Ehlers that isolates intermediate-frequency market cycles. It computes the difference between two 2-pole Butterworth high-pass filters with different cutoff periods, revealing the spectral band between the two cutoff frequencies.
+
+## Origin
+
+- **Author:** John F. Ehlers
+- **Source:** "Decyclers", Technical Analysis of Stocks & Commodities, September 2015
+- **Category:** Oscillator / Digital Signal Processing
+
+## Formula
+
+The DECO uses two 2-pole Butterworth high-pass filters:
+
+```
+α = (cos(0.707 × 2π/period) + sin(0.707 × 2π/period) - 1) / cos(0.707 × 2π/period)
+HP[n] = (1 - α/2)² × (x[n] - 2×x[n-1] + x[n-2]) + 2×(1-α) × HP[n-1] - (1-α)² × HP[n-2]
+
+DECO = HP_long - HP_short
+```
+
+The 0.707 factor (1/√2) places the filter response at the -3 dB Butterworth design point.
+
+### Transfer Function
+
+Each HP filter has the z-domain transfer function:
+
+```
+H(z) = (1-α/2)² × (1 - 2z⁻¹ + z⁻²) / (1 - 2(1-α)z⁻¹ + (1-α)²z⁻²)
+```
+
+The DECO output is the difference H_long(z) - H_short(z), which forms a bandpass response isolating cycles between the short and long cutoff periods.
+
+## Parameters
+
+| Parameter | Type | Default | Range | Description |
+|-----------|------|---------|-------|-------------|
+| shortPeriod | int | 30 | > 0 | Short HP cutoff period (bars) |
+| longPeriod | int | 60 | > shortPeriod | Long HP cutoff period (bars) |
+
+## Interpretation
+
+The Decycler Oscillator provides several analytical perspectives:
+
+- **Zero-Line Crossovers:**
+  - Crossing above zero indicates bullish cycle momentum
+  - Crossing below zero indicates bearish cycle momentum
+  - The zero-crossing timing is relatively lag-free
+
+- **Band Isolation:**
+  - The oscillator extracts only cycles within the frequency band defined by the two cutoff periods
+  - Shorter cycles and longer trends are both rejected
+  - This makes the oscillator highly selective
+
+- **Divergence Analysis:**
+  - Bullish divergence: price makes lower lows while DECO makes higher lows
+  - Bearish divergence: price makes higher highs while DECO makes lower highs
+  - Indicates potential trend reversal
+
+- **Multiple Instance Analysis:**
+  - Ehlers recommends using multiple DECO instances with different period pairs
+  - Crossovers between instances with different coefficients can identify trend reversals
+
+## Warmup Period
+
+The indicator requires `longPeriod` bars before producing reliable output. The first two bars always output zero (insufficient price history for the 2-pole HP filter).
+
+## Properties
+
+- **Range:** Unbounded (oscillates around zero)
+- **Complexity:** O(1) per bar (pure IIR filter, no lookback buffer needed)
+- **Memory:** O(1) — only stores filter state variables
+
+## Related Indicators
+
+- **Decycler (DECYCLER):** The low-pass complement — removes cycles, keeps trend
+- **SSF-DSP:** Similar concept using Super Smooth Filters instead of HP filters
+- **Roofing Filter:** HP + SSF combination for cycle isolation
+- **BandPass Filter:** Ehlers' direct bandpass approach
+
+## References
+
+1. Ehlers, J. F. (2015). "Decyclers." *Technical Analysis of Stocks & Commodities*, September 2015.
+2. Ehlers, J. F. (2013). *Cycle Analytics for Traders*. Wiley. Chapter 4.