v5.15.0

Reliable browser uploads, safer firmware-12 helper recovery, and an opt-in 7z decoder speed-up.

• Folder uploads now start from the self-hosted UI over plain HTTP. The
  browser build used a secure-context-only UUID API before it contacted the
  engine. Browsers hide that API on LAN addresses such as
  http://192.168.x.x:19113, leaving the task at “Starting…” forever. Upload,
  queue, and payload-playlist IDs now use the browser's LAN-safe cryptographic
  random source, with a compatibility fallback for older webviews. Once the
  engine accepts an upload, it continues independently if that browser tab is
  closed.

• The helper's rest-mode recovery is fail-closed on newer firmware. A
  network or manual clock correction can no longer be mistaken for a wake and
  trigger raw credential writes. Recovery now requires matching realtime and
  monotonic gaps plus a successful proof that no game is running. Unknown
  process layouts are rejected, failed elevation stops the sequence, and the
  detached watchdog no longer calls the mount scan that can hang on some
  firmware/loader combinations.

• 7z/LZMA2 uploads can opt into multiple decoder threads. The engine
  updates to sevenz-rust2 0.22.2 and lzma-rust2 0.20.1, and adds
  PS5UPLOAD_7Z_THREADS (1–16). It stays on one decoder thread by default,
  because multi-threaded LZMA2 decode is not free: the decoder splits work on
  dictionary-reset chunks and buffers each unit's decompressed output in
  memory. On a 2.5 GB test archive, peak RAM went from 74 MiB to 2.3 GiB for
  an archive packed with 7-Zip's own multithreading (about 24% faster), and to
  4.4 GiB with no speed-up at all for a solid archive — the RAM cost
  scales with the archive, not with the thread count, so a large game dump
  could exhaust memory. Turn it on if you are CPU-bound on a multi-threaded
  archive and have RAM to spare. File and shard order is unchanged either way,
  preserving byte correctness and resume safety.