feat: robust metric extraction with confidence score and proof snippets

- fixed Year-Prefix Bug in MetricParser
- added metric_confidence and metric_proof_text to database
- added Entity-Check and Annual-Priority to LLM prompt
- improved UI: added confidence traffic light and mouse-over proof tooltip
- restored missing API endpoints (create, bulk, wiki-override)

company-explorer/backend/scripts/migrate_db.py

@@ -54,6 +54,7 @@ def migrate_tables():
         comp_columns = get_table_columns(cursor, "companies")
         
         comp_migrations = {
+            "status": "TEXT", # Added to fix missing column error
             "calculated_metric_name": "TEXT",
             "calculated_metric_value": "FLOAT",
             "calculated_metric_unit": "TEXT",