fix: ensure robust PROJECT_ROOT path resolution in all test_run_folder scripts

test_run_folder/test_run_mortality.sh

@@ -2,10 +2,16 @@
 set -euo pipefail
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-export PYTHONPATH="$SCRIPT_DIR/src"
+if [ -d "$SCRIPT_DIR/../src" ]; then
+    PROJECT_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
+else
+    PROJECT_ROOT="$SCRIPT_DIR"
+fi
+cd "$PROJECT_ROOT"
+export PYTHONPATH="$PROJECT_ROOT/src"
 
-if [ -f "$SCRIPT_DIR/venv/bin/python" ]; then
-    PYTHON="$SCRIPT_DIR/venv/bin/python"
+if [ -f "$PROJECT_ROOT/venv/bin/python" ]; then
+    PYTHON="$PROJECT_ROOT/venv/bin/python"
 else
     PYTHON="python3"
 fi