Add GPU selection to job launcher

README.md

@@ -67,6 +67,10 @@ without changing the original training scripts. Starting any web job or
 dataset YOLO shortcut automatically opens its live log; the SSE stream resumes
 from the current log size after the initial tail so existing lines are not
 duplicated in the panel.
+The task builder also reads `GET /api/system/gpus` and lets an operator choose
+CPU or one or more GPUs before launch. Selected GPUs are passed to the backend
+as `gpus`, exported as `CUDA_VISIBLE_DEVICES`, and reflected into YOLO/visual
+`device` parameters and MMSeg config-generation `gpu_count/gpu_ids`.
 
 The coverage panel calls `GET /api/coverage` and verifies that the user-facing
 scripts from the existing `Seg/` workspace are mapped to web jobs. MMSeg