refactor: Code cleanup and documentation updates

Bug fixes:
- Fix ticket ID extraction using URLSearchParams instead of split()
- Add error handling for query result in get_users.php
- Make Discord webhook URLs dynamic (use HTTP_HOST)

Code cleanup:
- Remove debug console.log statements from dashboard.js and ticket.js
- Add getTicketIdFromUrl() helper function to both JS files

Documentation:
- Update Claude.md: fix web server (nginx not Apache), add new notes
- Update README.md: add keyboard shortcuts, update setup instructions

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Claude.md

@@ -23,14 +23,15 @@ Tinker Tickets is a feature-rich, self-hosted ticket management system built for
 - Backend: PHP 7.4+ with MySQLi
 - Frontend: Vanilla JavaScript, CSS3
 - Database: MariaDB on separate LXC (10.10.10.50)
-- Web Server: Apache on production (10.10.10.45)
+- Web Server: nginx with PHP-FPM on production (10.10.10.45)
 - Authentication: Authelia SSO with LLDAP backend
 
 **Production Environment:**
-- **Primary URL**: http://t.lotusguild.org
-- **Web Server**: Apache at 10.10.10.45 (`/root/code/tinker_tickets`)
+- **Primary URL**: https://t.lotusguild.org
+- **Web Server**: nginx at 10.10.10.45 (`/var/www/html/tinkertickets`)
 - **Database**: MariaDB at 10.10.10.50 (`ticketing_system` database)
 - **Authentication**: Authelia provides SSO via headers
+- **Dev Environment**: `/root/code/tinker_tickets` (not production)
 
 ## Architecture
 
@@ -105,7 +106,8 @@ Controllers → Models → Database
 │   ├── UserPreferencesModel.php          # User preferences
 │   └── WorkflowModel.php                 # Status transition workflows
 ├── scripts/
-│   └── cleanup_orphan_uploads.php        # Clean orphaned uploads
+│   ├── cleanup_orphan_uploads.php        # Clean orphaned uploads
+│   └── create_dependencies_table.php     # Create ticket_dependencies table
 ├── uploads/                              # File attachment storage
 ├── views/
 │   ├── admin/
@@ -195,6 +197,10 @@ All admin pages are accessible via the **Admin dropdown** in the dashboard heade
 7. **Cache busting**: Use `?v=YYYYMMDD` query params on JS/CSS files
 8. **Ticket linking**: Use `#123456789` in markdown-enabled comments
 9. **User groups**: Stored in `users.groups` as comma-separated values
+10. **API routing**: All API endpoints must be added to `index.php` router
+11. **Session in APIs**: RateLimitMiddleware starts session; don't call session_start() again
+12. **Database collation**: Use `utf8mb4_general_ci` (not unicode_ci) for new tables
+13. **Ticket ID extraction**: Use `getTicketIdFromUrl()` helper in JS files
 
 ## File Reference Quick Guide