v0.28.0

• Colour --net-only values in rustloc diff and rustloc commit: positive nets are green, negative nets red, and zero keeps the normal text colour. Applies to rows, totals, and skipped changes (#175).
• Make human count and diff tables easier to scan: column headers are centred over their values, columns are separated by two spaces instead of one, and the header and totals rules break at each column boundary (#177).
• Fix cargo install rustloc without --locked failing to compile after upstream releases of unicode-ident and salsa broke rust-analyzer's crates; rustloc now constrains those dependencies to compatible versions (#178).