feat: fetch and render charts for chat answers via /api/v1/charts

feat: sort analyses by updated_at, render data_used in traceability

fix: update traceability endpoint, remove retry logic, and fix report stale version

fix: stabilize analysis chat rendering and traceability

feat: refine analysis workspace navigation and theming

feat: polish workspace navigation and PWA branding

feat: implement dual-backend analysis workspace UX