Story-2000: Matter Brief page

The matter detail route now fills the existing Brief work mode with the authority-labeled Brief assembly from GET /app/matters/{id}/brief and the build liveness from GET /app/matters/{id}/frame-status. The Matter ribbon, Worknav, and Matter action rail remain the existing shell chrome.

States

• Empty first-run: neutral Brief status, record-first upload hero, editable placeholders, and real canonical case particulars.
• Preparing: blue liveness panel with elapsed time and “keep working” copy while the status hook polls queued/running builds.
• Ready: Brief summary, The dispute, Counsel's read, Case particulars, and per-field editable/provenance surfaces.
• Incomplete: amber status and missing-field invitation chips while the partial Brief remains readable.
• Stopped: red failure panel with retry/fallback/help actions; the workspace remains available.

Edit and ratify

Text fields reuse EditableSurface. Blur commits counsel edits through PATCH /app/matters/{id}/frame. Proposed fields show the existing confirm/reject affordance and call the generated accept/reject mutations.

Verification surface

Storybook stories seed the generated TanStack Query cache for all five states, so the same component and generated hooks render without Clerk or a live backend.

Known seam

The empty-state inline upload affordance is rendered as the Brief entry point. The full direct-to-S3 queue remains owned by the existing Matter action rail intake flow and is not duplicated in this Brief body.