Function render_transcript 

pub fn render_transcript(
    parts: &[OutputPart],
    program: &Program,
    line_tables: &[Vec<LineEntry>],
    resolver: Option<&dyn PluralResolver>,
    fragments: &[Fragment],
) -> Vec<(String, Vec<String>)>

Re-render a transcript against the given line tables.

Applies glue resolution, Spring spacing, and line trimming — the same pipeline as flush_lines — producing (text, tags) tuples per line.