## Summary

- Adds an editable COMPLETED DATE column to the Work Orders board table (after COMP DOC).
- Wires `completedDate` through board row typing, table-row mapping, and PATCH `field: "completedDate"`.
- Inline create keeps an empty placeholder (date is not set at creation).

## Scope

### In

- `completedDate` on `WorkOrderBoardRowApi` / `WorkOrderTableRow`
- Column + `DateCell` on board rows
- Scalar board patch expansion for `completedDate`
- Unit test for column order and patch op

### Out (follow-up PRs)

- Comp Doc dialog changes, closability gates, uplift, severity, filters, wizard

## API / BE

- Contract assumed: PATCH `/workorders/{id}/board` with `field: "completedDate"` already supported
- Confirm GET `/board` and `/board/search` rows include `completedDate` (see `docs/work-orders/pending-be-contract.md`)
- Blocked on BE: none for FE wiring (tolerates missing GET field as empty string)

## Test plan

- [ ] Board shows COMPLETED DATE column after COMP DOC
- [ ] Editing the cell PATCHes `completedDate`
- [ ] Inline create row shows placeholder for completed date
- [ ] `npm run verify` green locally

## Base

- Base branch: `dev`