fix(fileio): guard ratio progress display against divide-by-zero on empty input

[rootkiller6788]

Problem

When compressing an empty input with the xz/lzma (or gzip/lz4) format, the progress display divides by inFileSize, which is 0 for an empty file:

Read : 0 / 0 MB ==> inf%

This is a divide-by-zero (the CLI prints inf%, and nan% in related configurations) in FIO_compressLzmaFrame. The identical unguarded expression also exists in FIO_compressGzFrame and FIO_compressLz4Frame.

Fix

Guard the denominator so the ratio is computed only when inFileSize != 0, and display 0.00% otherwise:

inFileSize ? (double)outFileSize/(double)inFileSize*100 : 0

Applied consistently to the gzip, lzma/xz, and lz4 frame compressors.

Verification

Reproduced against the real code path (CLI built with lzma support):

• Before: zstd --format=xz -vv empty.txt prints Read : 0 / 0 MB ==> inf%
• After: the same command prints Read : 0 / 0 MB ==> 0.00%

Non-empty inputs are unaffected (the ternary falls through to the normal ratio).

Closes #4393