Batch Detail (`/batches/:batchId`)

Purpose

Present end-to-end context for a single batch: production metrics, gravity readings, packaging, pricing overrides, and activity history.
Allow brewers to update state, edit core properties, capture fermentation readings, and manage packaging lots from one screen.

Loads batch metadata via GET /batches/:id, packaging summaries via GET /packaging?batchId, and related beer/containers/pricebooks/team settings.
Requires access token tied to a team that owns the batch; write operations (state change, readings, packaging) enforce membership permissions.

Header actions: navigate back, open batch edit dialog, start a new batch copy, archive (placeholder until implemented).
Overview card exposes style, status toggle, public visibility, ABV/FG, volumes, allergens, tasting notes, and descriptive fields.
Gravity & ABV timeline handles viewing/editing fermentation readings, marking final gravity, and showing sparkline analytics.
Pricing section lets users toggle default containers, capture prices, and persist to pricebooks.
Packaging summary surfaces packaged lots, volumes, containers, and links to detailed packaging management; collapsible BBE card handles defaults.
Activity timeline card lists recent events (batches, packaging, state changes) for audit.
Badge management card supports upload/delete flows with validation and feedback.