Bytecode version diff should use a different rendering

[JakeWharton]

Today we're using a common diff helper, but it doesn't serve the content well.

BYTECODE VERSIONS:

   old │ new │ diff
  ─────┼─────┼───────────
   1   │ 1   │ 0 (+1 -1)

  + org.example.MainKt: 65

  - org.example.MainKt: 69

It should probably be something like

BYTECODE VERSIONS:

   version │ old │ new │ diff
  ─────────┼─────┼───────────
        65 │ 256 │ 255 │ -1 (0 -1)
        69 │   0 │   1 │ +1 (+1 0)

  org.example.MainKt: 65 → 69

Not sure whether we should show new types and their versions here. Maybe we combine with the types output?