Implement: <feature name>

Goal: <the outcome, in one sentence>
Where: <route(s) / component(s) / a provider in app/_components>
Reuse first: <which existing VUI pieces — RecordView, Dialog, Menu,
CommandPalette, ChartContainer — build on these, don't reinvent>
Behavior: <the rules — triggers, inputs, outputs, edge cases>
States: loading / empty / success / error (all required)
Data: <local state | a store | sessionStorage | your API>
Out of scope: <what NOT to build, so it stays focused>

Test scenarios (happy / unhappy) — generate the real cases from the behavior /
states above; this is only the shape:
TC-1 Trigger with valid input -> expected outcome
TC-2 Empty / no data -> empty state
TC-3 Failure (API / error) -> error surfaced, no crash
TC-4 Edge case <…> -> handled gracefully
TC-5 Re-trigger / idempotency -> no duplicate side effects

Done when: reuses existing components (no duplicate UI), tokens, a11y,
every state handled, the scenarios above pass, lint + types + build pass.