refact: Add named args to preprocess script

Author: andrewginns

agents_mcp_usage/evaluations/mermaid_evals/README.md

@@ -102,8 +102,8 @@ The local dashboard (`merbench_ui.py`) provides:
 ```bash
 # Convert CSV results to JSON format for the public Merbench website
 uv run agents_mcp_usage/evaluations/mermaid_evals/scripts/preprocess_merbench_data.py \
-  mermaid_eval_results/<timestamp>_combined_results.csv \
-  agents_mcp_usage/evaluations/mermaid_evals/results/<timestamp>_processed.json
+  -i "mermaid_eval_results/<timestamp>_combined_results.csv" \
+  -o "agents_mcp_usage/evaluations/mermaid_evals/results/<timestamp>_processed.json"
 ```
 
 ## Evaluation Task & Test Cases

agents_mcp_usage/evaluations/mermaid_evals/scripts/preprocess_merbench_data.py

@@ -2,13 +2,16 @@
 import pandas as pd
 import json
 import sys
+import argparse
+from datetime import datetime
 from pathlib import Path
 
 # Add parent directory to path to import modules
 sys.path.append(str(Path(__file__).parent.parent))
 
 from agents_mcp_usage.evaluations.mermaid_evals.dashboard_config import DEFAULT_CONFIG
 from agents_mcp_usage.evaluations.mermaid_evals.schemas import DashboardConfig
+from agents_mcp_usage.utils import get_project_root
 
 def parse_metric_details(metric_details_str):
     """Safely parse JSON string from Metric_details column."""
@@ -158,8 +161,29 @@ def extract_provider(model_name):
     return output_data
 
 def main():
-    csv_path = "/home/ubuntu/projects/agents-mcp-usage/mermaid_eval_results/Jun_gemini_results.csv"
-    output_path = "/home/ubuntu/projects/agents-mcp-usage/agents_mcp_usage/evaluations/mermaid_evals/results/Jun_gemini_results_processed.json"
+    parser = argparse.ArgumentParser(description="Process CSV evaluation results for static site")
+    parser.add_argument("-i", "--input_csv", nargs="?", help="Path to input CSV file", default=None)
+    parser.add_argument("-o", "--output_json", nargs="?", help="Path to output JSON file", default=None)
+    
+    args = parser.parse_args()
+    
+    project_root = get_project_root()
+    current_month = datetime.now().strftime("%b").lower()
+    
+    # Set default paths if not provided
+    if args.input_csv:
+        csv_path = Path(args.input_csv)
+        if not csv_path.is_absolute():
+            csv_path = project_root / csv_path
+    else:
+        csv_path = project_root / "mermaid_eval_results" / f"{current_month}_gemini_results.csv"
+    
+    if args.output_json:
+        output_path = Path(args.output_json)
+        if not output_path.is_absolute():
+            output_path = project_root / output_path
+    else:
+        output_path = project_root / "agents_mcp_usage" / "evaluations" / "mermaid_evals" / "results" / f"{current_month}_gemini_results_processed.json"
 
     print(f"Processing {csv_path}...")
     data = process_csv_for_static_site(csv_path)