Function calculate_chart_indicator_series 

pub fn calculate_chart_indicator_series(
    candles: &[Candle],
    indicators: &[String],
) -> HashMap<String, Vec<Option<f64>>>

Calculate chart indicator series based on a list of indicator names.

Supported indicator names:

• ema_20, ema_50, sma_20, sma_50
• bb_20_2 (returns bb_upper, bb_middle, bb_lower)
• rsi_14
• macd (returns macd_line, macd_signal, macd_histogram)
• stochastic (returns stoch_k, stoch_d)
• cci_20
• williams_r_14
• obv
• mfi_14