feat: add initial implementation of Kitchen CRM with authentication and dashboard features

- Create global styles and theme management
- Implement app shell layout with sidebar navigation
- Add authentication layout and pages for login and registration
- Develop dashboard page with placeholder content
- Introduce routing guards for guest-only and authenticated routes
- Set up Zustand for state management of authentication and theme
- Create API types and structures for CRM entities
- Configure Vite with PWA support and Tailwind CSS

frontend/src/config/env.ts

@@ -0,0 +1,24 @@
+const API_URL = import.meta.env.VITE_API_URL?.replace(/\/$/, '') || 'http://localhost:8000'
+const API_PREFIX = '/api/v1'
+const APP_NAME = 'Kitchen CRM'
+const ORG_HEADER = 'X-Organization-Id'
+
+export const env = {
+  APP_NAME,
+  API_URL,
+  API_PREFIX,
+  ORG_HEADER,
+  DASHBOARD_URL: import.meta.env.VITE_APP_URL || (typeof window !== 'undefined' ? window.location.origin : ''),
+}
+
+export const storageKeys = {
+  theme: 'kcrm-theme',
+  tokens: 'kcrm-auth-tokens',
+  user: 'kcrm-user',
+  activeOrg: 'kcrm-active-org',
+}
+
+export const pagination = {
+  defaultPageSize: 20,
+  maxPageSize: 100,
+}