Creates a new billing line configuration with the specified parameters.

Billing lines define what will be charged to tenants or landlords, either on a
recurring basis or as one-time charges. Each billing line is associated with appropriate
accounting accounts for financial tracking.

When creating a billing line, you must specify:

• The amount to be billed
• The transaction configuration defining the nature of the charge
• The associated leasing contract
• Start date for the billing line

The system uses the BillingLineFactory service to automatically:

• Associate the billing line with the appropriate debit and credit accounts
• Configure the billing line based on the transaction configuration
• Set up proper frequency and date range for the billing

To view available transaction configurations, use the GET /api/v1/transaction_configurations
endpoint.

The system will use these billing lines as templates to generate actual
accounting transactions when billing cycles occur.