feat: add test data generator script

Generate 35,000+ realistic test records:
- 12 data sources (PostgreSQL, MySQL, Oracle, SQL Server, DM)
- 31 databases, 863 tables, 17,152 columns
- 81 users across 13 departments
- 8 classification projects, 24 tasks
- 12,000 classification results with varied confidence levels
- 5,000 operation logs

Covers all insurance domains: policy, claim, customer, finance, channel, actuary, regulatory, vehicle

backend/scripts/check_sequences.py

@@ -0,0 +1,9 @@
+import sys
+sys.path.insert(0, '/Users/nathan/Work/DataPointer/prop-data-guard/backend')
+from app.core.database import engine
+from sqlalchemy import text
+
+with engine.connect() as conn:
+    result = conn.execute(text("SELECT sequencename FROM pg_sequences WHERE schemaname = 'public'"))
+    for row in result:
+        print(row[0])