feat: compute-sanitizer support in Argo training workflow

Usage: ./scripts/argo-train.sh dqn --baseline --epochs 2 --sanitizer memcheck
       ./scripts/argo-train.sh dqn --baseline --epochs 1 --sanitizer synccheck

Tools: memcheck (OOB, uninitialized), racecheck (data races),
synccheck (__syncthreads divergence/deadlocks).
10-100x slower — use with 1-2 epochs for debugging.
Detects exact kernel + line causing GPU hang.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/argo-train.sh

@@ -25,6 +25,7 @@ SYMBOL=""
 WATCH=false
 BASELINE=false
 CAPITAL=""
+SANITIZER="none"
 
 usage() {
   cat <<EOF
@@ -43,6 +44,7 @@ Options:
   --symbol <sym>       Trading symbol (default: ES.FUT)
   --capital <n>        Initial capital (default: 35000)
   --baseline           Skip hyperopt (trials=0)
+  --sanitizer <tool>   Run under compute-sanitizer (memcheck|racecheck|synccheck)
   --watch              Follow workflow logs
   -h, --help           Show this help
 EOF
@@ -68,6 +70,7 @@ while [[ $# -gt 0 ]]; do
     --symbol)    SYMBOL="$2"; shift 2 ;;
     --capital)   CAPITAL="$2"; shift 2 ;;
     --baseline)  BASELINE=true; shift ;;
+    --sanitizer) SANITIZER="$2"; shift 2 ;;
     --watch)     WATCH=true; shift ;;
     -h|--help)   usage ;;
     *)           echo "Unknown option: $1"; usage ;;
@@ -84,6 +87,7 @@ CMD="$CMD -p model=$MODEL"
 [[ -n "$GPU_POOL" ]]  && CMD="$CMD -p gpu-pool=$GPU_POOL"
 [[ -n "$SYMBOL" ]]    && CMD="$CMD -p symbol=$SYMBOL"
 [[ -n "$CAPITAL" ]]   && CMD="$CMD -p initial-capital=$CAPITAL"
+[[ "$SANITIZER" != "none" ]] && CMD="$CMD -p sanitizer=$SANITIZER"
 
 $BASELINE && CMD="$CMD -p hyperopt-trials=0"
 $WATCH    && CMD="$CMD --watch"