docs: update sidebar navigation documentation

Updated documentation to reflect new sidebar structure:
- Added Platform Administration section
- Added Customers page to navigation
- Updated page mapping table with all current pages
- Updated sidebar organization in page-templates.md
- Added customers logger to pre-configured loggers list

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

docs/frontend/shared/sidebar.md

@@ -160,8 +160,11 @@ function adminUsers() {
 | Page | JavaScript `currentPage` | Sidebar Check | URL |
 |------|--------------------------|---------------|-----|
 | Dashboard | `'dashboard'` | `x-show="currentPage === 'dashboard'"` | `/admin/dashboard` |
+| Companies | `'companies'` | `x-show="currentPage === 'companies'"` | `/admin/companies` |
 | Vendors | `'vendors'` | `x-show="currentPage === 'vendors'"` | `/admin/vendors` |
 | Users | `'users'` | `x-show="currentPage === 'users'"` | `/admin/users` |
+| Customers | `'customers'` | `x-show="currentPage === 'customers'"` | `/admin/customers` |
+| Marketplace | `'marketplace'` | `x-show="currentPage === 'marketplace'"` | `/admin/marketplace` |
 | Imports | `'imports'` | `x-show="currentPage === 'imports'"` | `/admin/imports` |
 | Components | `'components'` | `x-show="currentPage === 'components'"` | `/admin/components` |
 | Icons | `'icons'` | `x-show="currentPage === 'icons'"` | `/admin/icons` |
@@ -170,20 +173,34 @@ function adminUsers() {
 
 ### Updated Sidebar Structure
 
-The fixed sidebar now includes:
+The sidebar is organized into the following sections:
 
-**Main Navigation:**
+**Dashboard:**
 - Dashboard
+
+**Platform Administration:**
+- Companies
 - Vendors
 - Users
-- Import Jobs
+- Customers
+- Marketplace
 
-**Developer Tools Section:** (NEW!)
+**Content Management:**
+- Platform Homepage
+- Content Pages
+- Vendor Themes
+
+**Developer Tools:**
 - Components
 - Icons
 - Testing Hub
+- Code Quality
 
-**Settings Section:**
+**Platform Monitoring:**
+- Import Jobs
+- Application Logs
+
+**Settings:**
 - Settings
 
 Each section is properly separated with dividers and all menu items have active indicators.