weichen
c0f0200abd
Why: Land phase 4 of the UI redesign in the parent repo: ToolBlock chat contract, Collapsible migration of all folds, live sweep with worked-time, and the honest in-progress input hint. Completes the four-phase plan on this branch (deviation recorded in the task card). Evidence: combined make test -> go core/backend/agent-command ok, frontend 39 vitest passed, ui 66 vitest passed; tsc clean in both submodules. Impact: modules/ui and modules/frontend gitlinks move to their feature/ui-tokens-v3 heads; task card records results and remaining items. Refs: task feature/ui-tokens-v3.
ui
@ abc9858699