File Cabinet MVP: case detail with inline Ledger CRUD

- Extend Transaction with ledger fields (item_no, employee_number, t_code, t_type_l, quantity, rate, billed)
- Startup SQLite migration to add missing columns on transactions
- Ledger create/update/delete endpoints with validations and auto-compute Amount = Quantity × Rate
- Uniqueness: ensure (transaction_date, item_no) per case by auto-incrementing
- Compute case totals (billed/unbilled/overall) and display in case view
- Update case.html for master-detail ledger UI; add client-side auto-compute JS
- Enhance import_ledger_data to populate extended fields
- Close/Reopen actions retained; case detail sorting by date/item
- Auth: switch to pbkdf2_sha256 default (bcrypt fallback) and seed admin robustness

Tested in Docker: health OK, login OK, import ROLODEX/FILES OK, ledger create persisted and totals displayed.

app/database.py

@@ -12,6 +12,7 @@ from sqlalchemy import create_engine
 from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy.orm import sessionmaker, Session
 from dotenv import load_dotenv
+from sqlalchemy import inspect, text
 
 # Load environment variables from .env file
 load_dotenv()
@@ -68,6 +69,42 @@ def create_tables() -> None:
     """
     Base.metadata.create_all(bind=engine)
 
+    # Lightweight migration: ensure ledger-specific columns exist on transactions
+    try:
+        inspector = inspect(engine)
+        columns = {col['name'] for col in inspector.get_columns('transactions')}
+
+        migration_alters = []
+        # Map of column name to SQL for SQLite ALTER TABLE ADD COLUMN
+        required_columns_sql = {
+            'item_no': 'ALTER TABLE transactions ADD COLUMN item_no INTEGER',
+            'employee_number': 'ALTER TABLE transactions ADD COLUMN employee_number VARCHAR(20)',
+            't_code': 'ALTER TABLE transactions ADD COLUMN t_code VARCHAR(10)',
+            't_type_l': 'ALTER TABLE transactions ADD COLUMN t_type_l VARCHAR(1)',
+            'quantity': 'ALTER TABLE transactions ADD COLUMN quantity FLOAT',
+            'rate': 'ALTER TABLE transactions ADD COLUMN rate FLOAT',
+            'billed': 'ALTER TABLE transactions ADD COLUMN billed VARCHAR(1)'
+        }
+
+        for col_name, ddl in required_columns_sql.items():
+            if col_name not in columns:
+                migration_alters.append(ddl)
+
+        if migration_alters:
+            with engine.begin() as conn:
+                for ddl in migration_alters:
+                    conn.execute(text(ddl))
+    except Exception as e:
+        # Log but do not fail startup; migrations are best-effort for SQLite
+        try:
+            from .logging_config import setup_logging
+            import structlog
+            setup_logging()
+            _logger = structlog.get_logger(__name__)
+            _logger.warning("sqlite_migration_failed", error=str(e))
+        except Exception:
+            pass
+
     # Seed default admin user after creating tables
     try:
         from .auth import seed_admin_user