McMillan Volatility Bands (MVB) – with Entry Logic

// McMillan Volatility Bands (MVB) with signal + entry logic
// Author: ChatGPT for OneRyanAlexander
// Notes:
// - Bands are computed using percentage volatility (log returns), per the Black‑Scholes framing.
// - Inner band (default 3σ) and outer band (default 4σ) are configurable.
// - A setup occurs when price closes outside the outer band, then closes back within the inner band.
// The bar that re‑enters is the "signal bar." We then require price to trade beyond the signal bar's
// extreme by a user‑defined cushion (default 0.34 * signal bar range) to confirm entry.
// - Includes alertconditions for both setups and confirmed entries.