Make auto cleanup fast and clean

Changes:
- Suppress trace eraser output in auto mode (only show ✓)
- Clear screen after cleanup
- Leave user in /root directory
- Single success message

Result:
- Question -> yes -> quick cleanup -> ✓ All traces removed -> /root
- Fast, minimal output, clean exit

launcher.sh

@@ -1507,8 +1507,8 @@ main() {
                 read -p "Clean history and remove traces? (yes/no): " clean_hist
 
                 if [ "$clean_hist" = "yes" ]; then
-                    # Run trace eraser in non-interactive mode
-                    TRACE_ERASER_AUTO=yes bash "$BASE_DIR/tools/erase-toolkit-traces.sh"
+                    # Run trace eraser in non-interactive mode (suppress output)
+                    TRACE_ERASER_AUTO=yes bash "$BASE_DIR/tools/erase-toolkit-traces.sh" 2>&1 | grep -E "^✓|^$" || true
                 fi
 
                 echo ""