Mouillay GPU Miner 1.0.3-rc1 - RTX 50 series preview

This build adds a native Blackwell compute 12.0 (SM120) backend. Automatic
per-device routing keeps SM86 on RTX 30 and SM89 on RTX 40; RTX 50 uses
blackwell_sm120. Existing pool/wallet launchers work unchanged.

Windows: put MouillayMiner.exe and your START_MINER.bat in one writable folder.
Edit the pool and YOUR wallet.worker, then start the BAT. Logs go into logs/.
Use a current NVIDIA driver supporting CUDA 12.8 or newer.

Useful diagnostics (run beside the executable):
  MouillayMiner.exe --list-devices
  MouillayMiner.exe --mode validate --json-console
  MouillayMiner.exe --backend portable_v3 --mode validate --json-console
Linux: use ./MouillayMiner instead of MouillayMiner.exe. Requirements for the
native Linux build remain x86_64 / glibc 2.39+ (Ubuntu 24.04+).

The first command should select blackwell_sm120 on a GeForce RTX 50 GPU.
The second performs local GPU/oracle/Rust proof verification without a pool.
Mining refuses to continue if its startup digest self-test fails. Keep the
complete error and logs if validation fails, including the model and OS.

Implementation: integer U8 x U8 -> S32 Tensor Core MMA, rank128/K65536,
24x8 proof pattern, PAD4/base64 operands, in-kernel BLAKE3 and compact winning
digest capture. No FP16 conversion. Preparation and CPU proof service reused.
SM86/SM89 production kernels, gzip, share difficulty and developer fees unchanged.

Qualification: SM120 compiled with CUDA NVRTC 12.8. The same new source was
compiled for the local RTX 3070: digest equality, 16 Rust proofs, multiple
grids/jobs/targets, uint64 nonces and capture guards passed. Routing tests cover
mixed SM86/SM89/SM120 systems and binary-only packages.
No physical RTX 50 has been tested here; its hashrate and real-device behavior
remain to be confirmed. This is a test build, separate from the stable 1.0.2.

Docker:
  docker load -i Mouillay-GPU-Miner-1.0.3-rc1-docker-linux-amd64.tar.gz
  docker run --rm --gpus all -v mouillay-logs:/opt/mouillay/logs mouillay-gpu-miner:1.0.3-rc1 --pool poolmouillay.com:3360 --user YOUR_PEARL_ADDRESS.rig1