Function tile_path 

pub fn tile_path(
    level: u32,
    index: u64,
    width: u64,
) -> Result<String, TransparencyError>

Encode a tile path per C2SP tlog-tiles spec.

Segments are zero-padded to 3 digits. Non-final segments get an x prefix. E.g., index 1234067 → x001/x234/067.

Args:

• level — Tile level (0 for data tiles, 1+ for hash tiles).
• index — Tile index at the given level.
• width — Partial tile width (0 means full tile, i.e., 256).

Usage:

let path = tile_path(0, 1234067, 0)?;
assert_eq!(path, "tile/0/x001/x234/067");