refactor: rename marketplace to storefront across the entire monorepo

Comprehensive rename of all marketplace references to storefront:
- API module: apps/api/src/modules/marketplace/ → storefront/
- Components: MarketplaceHeader → StorefrontHeader, MarketplaceShell →
  StorefrontShell, MarketplaceFooter → StorefrontFooter
- Types: marketplace-homepage.ts → storefront-homepage.ts
- Test files: employee-marketplace-* → employee-storefront-*
- All source code identifiers, imports, route paths, and strings
- Documentation (docs/), CI config (.gitlab-ci.yml), scripts
- Dashboard, admin, storefront workspace references
- Prisma field names preserved (isListedOnMarketplace, marketplaceRating,
  marketplaceFunnelEvent) as they map to database schema

Validation:
- API type-check: 0 errors
- Storefront type-check: 0 errors
- Dashboard type-check: 0 errors
- Full monorepo type-check: only pre-existing admin TS18046

apps/api/src/tests/integration/public-validation-boundaries.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest'
 import { parseBody, parseQuery } from '../../http/validate'
-import { marketplaceReservationSchema, paginationSchema } from '../../modules/marketplace/marketplace.schemas'
+import { storefrontReservationSchema, paginationSchema } from '../../modules/storefront/storefront.schemas'
 import { paySchema } from '../../modules/site/site.schemas'
 
 function reqWith(body: unknown, query: unknown = {}) {
@@ -8,7 +8,7 @@ function reqWith(body: unknown, query: unknown = {}) {
 }
 
 describe('public validation boundaries', () => {
-  it('keeps marketplace pagination coercion consistent with route parsing', () => {
+  it('keeps storefront pagination coercion consistent with route parsing', () => {
     expect(parseQuery(paginationSchema, reqWith({}, { page: '4', pageSize: '25' }))).toEqual({
       page: 4,
       pageSize: 25,
@@ -24,8 +24,8 @@ describe('public validation boundaries', () => {
     }))).toThrow('Invalid enum value')
   })
 
-  it('requires enough anonymous marketplace reservation identity to create a booking request', () => {
-    const parsed = parseBody(marketplaceReservationSchema, reqWith({
+  it('requires enough anonymous storefront reservation identity to create a booking request', () => {
+    const parsed = parseBody(storefrontReservationSchema, reqWith({
       vehicleId: 'ckvvehicle000000000000001',
       companySlug: 'atlas-cars',
       firstName: 'Aya',