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/db/schema/stores.ts

@@ -5,7 +5,14 @@ export const companies = pgTable('company', {
   name: varchar('name', { length: 255 }).notNull(),
   phone: varchar('phone', { length: 50 }),
   email: varchar('email', { length: 255 }),
+  address: jsonb('address').$type<{
+    street?: string
+    city?: string
+    state?: string
+    zip?: string
+  }>(),
   timezone: varchar('timezone', { length: 100 }).notNull().default('America/Chicago'),
+  logoFileId: uuid('logo_file_id'),
   notes: text('notes'),
   createdAt: timestamp('created_at', { withTimezone: true }).notNull().defaultNow(),
   updatedAt: timestamp('updated_at', { withTimezone: true }).notNull().defaultNow(),
@@ -13,9 +20,6 @@ export const companies = pgTable('company', {
 
 export const locations = pgTable('location', {
   id: uuid('id').primaryKey().defaultRandom(),
-  companyId: uuid('company_id')
-    .notNull()
-    .references(() => companies.id),
   name: varchar('name', { length: 255 }).notNull(),
   address: jsonb('address').$type<{
     street?: string