Function measure_sequence 

pub fn measure_sequence(score: &Score) -> Vec<usize>

Returns the ordered list of physical measure indices to play back, expanding repeat sections, volta brackets, and navigation marks.

Handles:

• RepeatStart / RepeatEnd / RepeatBoth barlines
• First/second-ending volta brackets
• DaCapo, DaCapoAlFine, DaCapoAlCoda
• DalSegno, DalSegnoAlFine, DalSegnoAlCoda
• Fine, ToCoda, Coda markers

Limitations: single-level repeats; during a D.C./D.S. return pass, all barline repeats and voltas are ignored (safe linear fallback).