🐛 Clean output directory before profiling runs

Previously, run-profiled-test.sh would create the output directory
with mkdir -p but not clean up existing files. This caused old profile
files to remain and potentially confuse analysis when mixing
single-component and multi-component data.

Now the script:
- Warns if the output directory already exists
- Removes the entire directory to start fresh
- Creates a clean directory for the new profiling run

This ensures each test run has clean, isolated data.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: tmshort

hack/tools/memory-profiling/run-profiled-test.sh

@@ -47,7 +47,12 @@ log_warn() {
     echo -e "${YELLOW}[WARN]${NC} $*"
 }
 
-# Create output directory
+# Create output directory (clean up if it exists)
+if [ -d "${OUTPUT_DIR}" ]; then
+    log_warn "Output directory already exists: ${OUTPUT_DIR}"
+    log_warn "Removing old profiles to start fresh..."
+    rm -rf "${OUTPUT_DIR}"
+fi
 mkdir -p "${OUTPUT_DIR}"
 
 # Update OUTPUT_DIR_ABS now that directory exists