The wreq dependency was declared without the gzip, brotli, deflate and zstd
features, so the stealth client returned bodies still compressed while the
reqwest path decoded them. The Chrome145 emulation advertises those encodings,
so origins do compress, and the raw gzip bytes reached the HTML parser as
document text.
Add a regression test that serves one gzip response and asserts the stealth
client decodes it.
Fixes#563.
