Client and company detail pages each gain an Addresses tab with click-to-edit
fields wired to the existing CountryCombobox/SubdivisionCombobox primitives.
Adds a primary toggle that demotes the previous primary inside one transaction
so the partial unique index never trips.
- New service helpers: list/add/update/remove ClientAddress + CompanyAddress
- New routes: /api/v1/clients/[id]/addresses[/addressId], same under companies/
- New shared component: <AddressesEditor> reused by both detail surfaces
- Integration tests cover happy path, primary demotion, and tenant scoping
Tests: 747/747 vitest (was 741, +6 address tests).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>