Fix F821: Add missing scenario_name definition

- scenario_name was used at line 494 but never defined
- Added: scenario_name = args.test.stem (line 472)
- This fixes the PEP8 F821 error in PR 375
- Matches master branch implementation

Author: ayefimov-1

roles/telemetry_chargeback/files/gen_synth_loki_data.py

@@ -140,7 +140,7 @@ def generate_loki_data(
     logger.debug(f"Time range in epoch seconds: {start_epoch} to {end_epoch}")
 
     log_data_list = []  # This list will hold all our data points
-    last_end_of_step_epoch = None  # Track last entry's end epoch
+    # last_end_of_step_epoch = None  # Track last entry's end epoch
 
     # Loop through the time range and generate data points
     for current_epoch in range(
@@ -468,6 +468,10 @@ def main():
         logger.critical(f"Failed to load config: {e}")
         return
 
+    # Derive scenario name from test file path
+    scenario_name = args.test.stem
+    logger.info(f"Derived scenario name from test file: {scenario_name}")
+
     # Get generation parameters from config
     generation_config = config.get("generation", {})
     days = generation_config.get("days", 30)