some webUI fixes

python_app/storage/npz/store.py

@@ -27,6 +27,15 @@ from python_app.storage.store_api import StoreApi
 logger = logging.getLogger(__name__)
 
 
+def _compose_snapshot_stem(name: str, name_prefix: str) -> str:
+    """Compose a sanitized snapshot stem from an optional prefix and the operator's name.
+
+    The name falls back to a UTC timestamp when blank, so a save is always uniquely named.
+    """
+    base = name.strip() or datetime.now(timezone.utc).strftime("snapshot_%Y%m%d_%H%M%S")
+    return sanitize_path_component(f"{name_prefix}_{base}" if name_prefix else base)
+
+
 class NpzStore(StoreApi):
     """Persist preprocess sets and runtime snapshots using NumPy files."""
 
@@ -193,13 +202,14 @@ class NpzStore(StoreApi):
         preprocessed_history: list[SweepCollection],
         result_history: list[ResultCollection],
         last_n: int,
+        *,
+        name_prefix: str = "",
     ) -> tuple[Path, dict[str, Any]]:
         """Save historical runtime collections in NumPy tree format."""
         if last_n <= 0:
             raise ValueError("last_n must be > 0")
 
-        snapshot_stem = snapshot_name.strip() or datetime.now(timezone.utc).strftime("snapshot_%Y%m%d_%H%M%S")
-        snapshot_stem = sanitize_path_component(snapshot_stem)
+        snapshot_stem = _compose_snapshot_stem(snapshot_name, name_prefix)
 
         output_root_dir.mkdir(parents=True, exist_ok=True)
         snapshot_dir = output_root_dir / snapshot_stem
@@ -324,13 +334,13 @@ class NpzStore(StoreApi):
         *,
         channel: str = "s21",
         primary_stage: str = "preprocessed",
+        name_prefix: str = "",
     ) -> tuple[list[Path], dict[str, Any]]:
         """Save one runtime VNA-history JSON per available combo."""
         if last_n <= 0:
             raise ValueError("last_n must be > 0")
 
-        output_stem = output_name.strip() or datetime.now(timezone.utc).strftime("snapshot_%Y%m%d_%H%M%S")
-        output_stem = sanitize_path_component(output_stem)
+        output_stem = _compose_snapshot_stem(output_name, name_prefix)
         output_root_dir.mkdir(parents=True, exist_ok=True)
         output_dir = self._vna_json_output_dir(output_root_dir, output_stem)
         output_dir.mkdir(parents=True, exist_ok=True)