feat(work-items): display work orders in the same format as invoices

[Dev869]

What changed

The Work Orders list (/dashboard/work-items) now renders in the exact same visual format as the Invoices list (/dashboard/invoices) — a bordered, column-driven data table with a select-all checkbox, uppercase header row, hover/selected row states, status pills, and AI insight badges — instead of the previous stacked card layout.

Shared component

Extracted a single source of truth so both lists stay visually identical:

• web/src/components/common/EntityTable.tsx (new) — generic, column-driven table that reproduces the original InvoiceTable markup and styling exactly (same bordered container, header style, checkbox column, row hover/selected treatment, empty-state row).
• web/src/components/finance/InvoiceTable.tsx (refactored) — now a thin column-config wrapper around EntityTable. Visual output is unchanged (same columns: Work Order / Client, Amount, Sent Date, Due Date, Status + invoice risk insight badges).
• web/src/components/workitems/WorkItemTable.tsx (new) — Work Orders column config for the same EntityTable.

Field mapping (work-order columns mirror the invoice columns)

Invoice column	Work Order column
Work Order / Client	Work Order / Client (subject + client; app tag + Non-Billable tag as subtext)
Amount	Cost (right-aligned, mono, tabular)
Sent Date	Hours (right-aligned, mono, tabular)
Due Date	Created (date)
Status (pill + risk)	Status (StatusBadge + client-approval pill + completion-estimate / scope-creep insight badges)

Preserved Work Orders functionality

• Status tabs (default Open) and type tabs
• Search box
• Advanced filters (client chips/dropdown, app chips/dropdown, date range, clear-all, URL sync)
• Multi-select with bulk Approve / Convert to Invoice / Archive (selection now driven by the shared table's checkboxes)
• CSV export
• New Work Order modal
• AI insight badges (completion estimate, scope creep) — now shown in the Status column
• Click row → navigate to work item detail (/dashboard/work-items/:id)
• Empty state unchanged

Not changed

• Invoices list (visual output identical — verified by intent diff: same columns, classes, status colors, insight badges)
• Data model, predicates (isWorkOrder / isInvoice), routing
• WorkItemCard (still used by Dashboard, ClientDetail, AppDetail)

Test plan

• npx tsc -b — exit 0
• npx eslint on all touched files — 0 errors
• npx vitest run — 70/70 passing
• Manual: verify Work Orders list visually matches Invoices list, all tabs/filters/bulk actions/export/modal work, row click navigates to detail

[github-actions]

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