MACD Crossover with Supertrend Filter

This script is a custom trading indicator that generates **buy and sell signals** based on the combination of:

### 🔹 MACD Crossover:

* **Long (Buy)** signal: when the MACD line crosses above the signal line **below the 0 line**.
* **Short (Sell)** signal: when the MACD line crosses below the signal line **above the 0 line**.

### 🔹 Supertrend Filter:

* **Only buy** when the Supertrend is **bullish (green)**.
* **Only sell** when the Supertrend is **bearish (red)**.

### 🔹 Additional Features:

* Plots green or red arrows on the chart for entries.
* Supertrend line is color-coded.
* Alerts can be enabled for both long and short signals.

✅ This combination filters MACD signals using trend direction for more reliable entries.