Function write_leaf 

pub fn write_leaf(
    writer: &mut impl Write,
    path: &Path,
    stat: &Stat,
    content: &LeafContent<impl FsVerityHashValue>,
    nlink: usize,
) -> Result

Writes a leaf node (non-directory) entry to the dumpfile format.

Handles all types of leaf nodes including regular files (inline and external), device files, symlinks, sockets, and FIFOs.