Text sizing: span width (w), packed sub-cell runs, TextSizing converter, wide-glyph guarantee - #74

Ambiguous reference in cref attribute: 'Write'. Assuming 'Cursorial.Output.TextSizingWriter.Write(System.Buffers.IBufferWriter<byte>, in Cursorial.Text.TextSizing, System.ReadOnlySpan<char>)', but could have also matched other overloads including 'Cursorial.Output.TextSizingWriter.Write(System.Buffers.IBufferWriter<byte>, in Cursorial.Text.TextSizing, byte, System.ReadOnlySpan<char>)'.