Currency Weekend - shading weekend trading

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// © 2025, Steve / Steven Anthony – "Currency Weekend"
// This script highlights the low-liquidity weekend window that often affects
// both fiat currency markets and cryptocurrencies like Bitcoin.
//
// ╭─────────────────────────────── DESCRIPTION ───────────────────────────────╮
// | This indicator shades a customizable time window on your chart, |
// | originally set to highlight the **forex weekend lull** from |
// | **Friday 21:00 UTC to Sunday 21:00 UTC**, when traditional fiat |
// | currency markets close. |
// | |
// | Traders who observe Bitcoin, Ethereum, or other crypto assets may |
// | notice reduced liquidity or increased erratic moves during this time, |
// | due to overlapping behaviors from professional forex traders who |
// | trade both markets. |
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//
// 🔧 Flexible Configuration:
// - Define your own start and end **day + time** for shading
// - Useful for shading other custom quiet periods or session transitions
//
// 💡 Use Cases:
// - Avoid trading during low-liquidity periods
// - Spot potential weekend traps or price gaps
// - Align crypto behavior with fiat market hours
//
// 📍 Default Settings:
// - Start: Friday 21:00 UTC
// - End: Sunday 21:00 UTC
//
// Timezone is normalized to the chart’s timezone for seamless integration.
//
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