Context

Implement the budget and cost tracking domain models per DESIGN_SPEC Section 10.

Models to Implement

• BudgetConfig - total monthly, alerts, per-task limit, per-agent daily limit, auto-downgrade (DESIGN_SPEC 10.4)
• BudgetHierarchy - company → department → team allocation (DESIGN_SPEC 10.1)
• CostRecord - per-API-call tracking (DESIGN_SPEC 10.2)
• SpendingSummary - aggregated spending by agent, department, time period

Acceptance Criteria

• Models match DESIGN_SPEC 10.1-10.4
• Budget allocation percentages validate to 100%
• Cost records are immutable (append-only pattern)
• Unit tests

Dependencies

• Core entity models issue (M1)

Design Spec Reference

Sections 10.1, 10.2, 10.4