docs: improve CI and testing documentation (#21202)

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

scripts/ci/amd/check_vram_clear.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+
+check_vram_clear() {
+    local vram_threshold_percent=5  # Allow up to 5% VRAM usage
+    local memory_threshold_mb=500   # Allow up to 500MB memory usage
+
+    if command -v rocm-smi >/dev/null 2>&1; then
+        echo "Checking ROCm GPU VRAM usage..."
+        # Check if any GPU has more than threshold VRAM allocated
+        local high_usage=$(rocm-smi --showmemuse | grep -E "GPU Memory Allocated \(VRAM%\): ([6-9]|[1-9][0-9]|100)")
+        if [ -n "$high_usage" ]; then
+            echo "ERROR: VRAM usage exceeds threshold (${vram_threshold_percent}%) on some GPUs:"
+            echo "$high_usage"
+            rocm-smi --showmemuse
+            return 1
+        else
+            echo "✓ VRAM usage is within acceptable limits on all GPUs"
+            return 0
+        fi
+   fi
+}
+
+# If this script is run directly (not sourced), run the check
+if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+    set -e
+    check_vram_clear
+fi