- Install recharts@3.8.1 as dependency
- Create chart-utils.ts with 4 exported pure functions: aggregateRunsByDay, aggregateCostsByDay, aggregateAgentWorkload, formatShortDate
- Create dashboard-charts.test.ts with 16 unit tests covering all aggregation behaviors
- All tests pass: 14-day bucketing with zero-fill, timed_out/interrupted as failed, null cost handling, top-8 + Others grouping, name truncation
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
ZacharyZhang-NY
