Post 9/21 EMA Cross — Paint X Bars

* Watches for **9 EMA crossing the 21 EMA** (a classic momentum/trend trigger).
* When a cross happens, it **paints exactly X bars** after the cross in a color you choose:

* **Bullish cross (9 > 21):** paints your bullish color for X bars.
* **Bearish cross (9 < 21):** paints your bearish color for X bars.
* You decide whether the **cross bar itself counts** as the first painted bar.
* Optionally plots the 9 & 21 EMAs so you can see the cross visually.

# Why that’s useful

* **Focus:** It reduces noise by spotlighting the **immediate post‑cross window** when momentum often continues.
* **Discipline:** “Exactly X bars” forces consistency, avoiding “just one more bar” bias.
* **Speed:** Color‑coded candles make it easy to scan charts fast (great for intraday work).

# How signals are defined

* **Bullish condition:** `ta.crossover(EMA9, EMA21)` — the fast EMA crosses **up** through the slow EMA.
* **Bearish condition:** `ta.crossunder(EMA9, EMA21)` — the fast EMA crosses **down** through the slow EMA.

# Key inputs (and what they control)

* **Fast EMA Length (default 9)** and **Slow EMA Length (default 21)**
Change these if your system uses different lookbacks (e.g., 8/21 or 10/20).
***CURRENTLY THE EMA REMAINS STATIC ON THE CHART. PLOT EMA FROM EXTERNAL INDICATOR FOR NOW
* **Bars to Paint After a Cross (default 5)**
How many bars get highlighted post‑cross.
* **Include the Cross Bar Itself? (default off)**
Turn on if you want painting to start **on** the cross candle; off to start **after** it.
* **Bullish/Bearish Paint Colors**
Set your preferred colors (e.g., green/red).
* **Plot EMAs on Chart?**
If off, the logic still works; it just hides the EMA lines.

# What you’ll see on the chart

* Candles **recolored** for exactly X bars after each cross, matching the direction.
* (Optional) 9 & 21 EMA lines so you can confirm the cross visually.
* When the X‑bar window ends, candles return to normal until the **next** cross.

# Practical trading uses

* **Entry timing:** Consider entries only during the painted window to align with fresh momentum.
* **Scaling logic:** Scale in/out within the painted window; stop adding when painting ends.
* **Context filter:** Use the paint as a **“go / no‑go” overlay** on top of your pattern or level setups (breakouts, pullbacks to EMA, ORB, etc.).