Thread init_mode and use_rslora through the scheduler's config parsing,
experiment record, and _train_inner call. Default alpha changed to 2*rank
to match trainer. Add pissa_sweep.json with 7 experiments ablating PiSSA
init vs standard, rsLoRA scaling, and learning rate variations at rank 128.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>