Add store settings page with location management

Company table gains address and logo_file_id columns. New store
settings API: GET/PATCH /store for company info, full CRUD for
/locations. Settings page shows store name, phone, email, address,
timezone with inline edit. Location cards with add/edit/delete.
Settings link in admin sidebar. Fixes leftover company_id on
location table and seed files.

packages/backend/src/test/helpers.ts

@@ -38,7 +38,6 @@ export async function seedTestCompany(app: FastifyInstance): Promise<void> {
   })
   await app.db.insert(locations).values({
     id: TEST_LOCATION_ID,
-    companyId: TEST_COMPANY_ID,
     name: 'Test Location',
   })