An sd0 buffer could hold any number of chunks, and each chunk grew the
inflated data by a full chunk whatever it held, so the data of a chunk
that was not full was followed by a gap. A buffer now holds at most
4096 chunks and inflates to at most 64 MiB, and every chunk is inflated
right after the one before it.
Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>
Sd0 gets a default constructor and Sd0::Compress(data), the raw sd0 bytes of
some data (what the client reads for UGC files it downloads without 3D
services). FromData compresses into a heap buffer big enough for a chunk that
grows when deflated (it used a 256 KiB stack buffer, so random data failed and
workers carried a large stack frame), and drops a half-written result.
Tests: chunks as the 1.10.64 client inflates them, incompressible data, empty.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
