feat: Add comprehensive documentation suite and reorganize project structure

- Created complete documentation in docs/ directory
- Added PROJECT_OVERVIEW.md with feature highlights and getting started guide
- Added ARCHITECTURE.md with system design and technical details
- Added SECURITY.md with comprehensive security implementation guide
- Added DEVELOPMENT.md with development workflows and best practices
- Added DEPLOYMENT.md with production deployment instructions
- Added API.md with complete REST API documentation
- Added CONTRIBUTING.md with contribution guidelines
- Added CHANGELOG.md with version history and migration notes
- Reorganized all documentation files into docs/ directory for better organization
- Updated README.md with proper documentation links and quick navigation
- Enhanced project structure with professional documentation standards

__install/README_FIX.txt

@@ -0,0 +1,31 @@
+EasyStream Database Configuration Fix
+====================================
+
+If you're getting the error:
+"Warning: Undefined array key \"new_layout\" in /srv/easystream/f_core/config.smarty.php on line 44"
+
+This means some database configurations are missing. To fix this:
+
+OPTION 1: Run the PHP fix script
+--------------------------------
+1. Navigate to your EasyStream installation directory
+2. Run: php __install/fix_database.php
+
+OPTION 2: Run the SQL script manually
+------------------------------------
+1. Import the SQL file into your database:
+   mysql -u your_username -p your_database < __install/fix_missing_config.sql
+
+OPTION 3: Add manually via phpMyAdmin or similar
+-----------------------------------------------
+Execute this SQL query in your database:
+
+INSERT IGNORE INTO `db_settings` (`cfg_name`, `cfg_data`, `cfg_info`) VALUES 
+('new_layout', '1', 'backend: enable/disable new layout menu'),
+('short_module', '1', 'backend: enable/disable video shorts'),
+('short_uploads', '1', 'backend: enable/disable video shorts uploads'),
+('channel_memberships', '0', 'backend: enable/disable channel memberships'),
+('member_chat_only', '0', 'backend: enable/disable member-only chat'),
+('member_badges', '0', 'backend: enable/disable member badges');
+
+After applying the fix, the control panel should be accessible without errors.