Phase 01: Semantic Position Model - 2 plans in 2 waves - Wave 1: SortOrderProvider + Trip day derivation (parallel-ready) - Wave 2: Tests verifying persistence behavior Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Phase 1: Semantic Position Model - Standard stack identified (SwiftData, Double sortOrder, CloudKit) - Architecture patterns documented (semantic position, midpoint insertion) - Pitfalls catalogued (row index confusion, precision exhaustion) - Existing codebase analysis confirms good foundation Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Phase 01: Semantic Position Model - Implementation decisions documented - Phase boundary established