## Restructured to Vertical Slices Cancelled original 8 subtasks (horizontal layers) and replaced with 3 vertical slices: **Old approach (cancelled):** - Phase 1: All backend (no UI) - not verifiable - Phase 2: All frontend - delayed value **New approach:** | Slice | Ticket | Deliverable | Verification | |-------|--------|-------------|--------------| | 1 | #109 | Operator chat end-to-end | Open session → send message → see in UI | | 2 | #110 | Guest chat (extends #109) | Guest + operator can chat bidirectionally | | 3 | #111 | History review (polish) | View chat transcript after session ends | Each slice is independently deployable and verifiable by actually using the feature.