Stack release: trueno 0.14.6 → realizar 0.6.14 → aprender 0.25.8.
Includes GH-238 (ONNX), GH-243 (quantize --plan), GH-246 (MLX size),
GH-261 (GPU fallback), GH-259 (APR GPU serve), GH-159 (conv layout),
and file splitting refactor (all files <500 lines).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>