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

f_core/f_functions/functions.security.php

@@ -0,0 +1,169 @@
+<?php
+/*******************************************************************************************************************
+| Software Name        : EasyStream
+| Software Description : High End YouTube Clone Script with Videos, Shorts, Streams, Images, Audio, Documents, Blogs
+| Software Author      : (c) Sami Ahmed
+|*******************************************************************************************************************
+|
+|*******************************************************************************************************************
+| This source file is subject to the EasyStream Proprietary License Agreement.
+| 
+| By using this software, you acknowledge having read this Agreement and agree to be bound thereby.
+|*******************************************************************************************************************
+| Copyright (c) 2025 Sami Ahmed. All rights reserved.
+|*******************************************************************************************************************/
+
+defined('_ISVALID') or header('Location: /error');
+
+/**
+ * Security helper functions
+ */
+
+/**
+ * Secure output escaping for templates
+ * @param string $string String to escape
+ * @return string Escaped string
+ */
+function secure_output($string)
+{
+    return VSecurity::escapeOutput($string);
+}
+
+/**
+ * Secure JavaScript output escaping
+ * @param string $string String to escape for JS
+ * @return string Escaped string
+ */
+function secure_js($string)
+{
+    return VSecurity::escapeJS($string);
+}
+
+/**
+ * Generate CSRF token field for forms
+ * @param string $action Action name
+ * @return string HTML input field
+ */
+function csrf_field($action = 'default')
+{
+    return VSecurity::getCSRFField($action);
+}
+
+/**
+ * Validate CSRF token from current request
+ * @param string $action Action name
+ * @return bool True if valid
+ */
+function validate_csrf($action = 'default')
+{
+    return VSecurity::validateCSRFFromPost($action);
+}
+
+/**
+ * Get secure parameter from GET
+ * @param string $key Parameter name
+ * @param string $type Parameter type
+ * @param mixed $default Default value
+ * @param array $options Validation options
+ * @return mixed Sanitized value
+ */
+function get_param($key, $type = 'string', $default = null, $options = [])
+{
+    return VSecurity::getParam($key, $type, $default, $options);
+}
+
+/**
+ * Get secure parameter from POST
+ * @param string $key Parameter name
+ * @param string $type Parameter type
+ * @param mixed $default Default value
+ * @param array $options Validation options
+ * @return mixed Sanitized value
+ */
+function post_param($key, $type = 'string', $default = null, $options = [])
+{
+    return VSecurity::postParam($key, $type, $default, $options);
+}
+
+/**
+ * Check rate limiting
+ * @param string $key Unique identifier
+ * @param int $maxAttempts Maximum attempts
+ * @param int $timeWindow Time window in seconds
+ * @return bool True if within limits
+ */
+function check_rate_limit($key, $maxAttempts = 10, $timeWindow = 300)
+{
+    return VSecurity::checkRateLimit($key, $maxAttempts, $timeWindow);
+}
+
+/**
+ * Validate file upload securely
+ * @param array $file $_FILES array element
+ * @param array $allowedTypes Allowed MIME types
+ * @param int $maxSize Maximum file size
+ * @return array Validation result
+ */
+function validate_file_upload($file, $allowedTypes = [], $maxSize = 10485760)
+{
+    return VSecurity::validateFileUpload($file, $allowedTypes, $maxSize);
+}
+
+/**
+ * Log security events
+ * @param string $event Event description
+ * @param array $context Additional context
+ */
+function log_security_event($event, $context = [])
+{
+    $logger = VLogger::getInstance();
+    $logger->logSecurityEvent($event, $context);
+}
+
+/**
+ * Log application errors with context
+ * @param string $message Error message
+ * @param array $context Additional context
+ */
+function log_app_error($message, $context = [])
+{
+    $errorHandler = VErrorHandler::getInstance();
+    $errorHandler->logApplicationError($message, $context);
+}
+
+/**
+ * Log validation errors
+ * @param string $field Field name
+ * @param mixed $value Field value
+ * @param string $rule Validation rule
+ * @param array $context Additional context
+ */
+function log_validation_error($field, $value, $rule, $context = [])
+{
+    $errorHandler = VErrorHandler::getInstance();
+    $errorHandler->logValidationError($field, $value, $rule, $context);
+}
+
+/**
+ * Log authentication errors
+ * @param string $message Error message
+ * @param string $username Username (if available)
+ * @param array $context Additional context
+ */
+function log_auth_error($message, $username = null, $context = [])
+{
+    $errorHandler = VErrorHandler::getInstance();
+    $errorHandler->logAuthError($message, $username, $context);
+}
+
+/**
+ * Log performance issues
+ * @param string $message Performance issue description
+ * @param float $executionTime Execution time in seconds
+ * @param array $context Additional context
+ */
+function log_performance_issue($message, $executionTime, $context = [])
+{
+    $logger = VLogger::getInstance();
+    $logger->logPerformanceIssue($message, $executionTime, $context);
+}