Implement Rate Limiter and Retry Mechanism for ManagedCode.Communication

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This PR implements a comprehensive Rate Limiter and Retry Mechanism for the ManagedCode.Communication library, providing robust control over request flow and automatic failure recovery.

🚀 Features Added

Rate Limiter

• Token Bucket Implementation: Configurable request limits with time windows (e.g., 10 requests per minute)
• Queue Management: Requests can be queued when rate limit is exceeded or rejected immediately
• Real-time Feedback: Provides current usage, available permits, and time until reset
• Thread-safe: Proper concurrency handling for multi-threaded scenarios

Retry Mechanism

• Flexible Retry Policies: Configurable max retries, intervals, and backoff strategies
• Multiple Backoff Strategies: Fixed, Linear, and Exponential backoff support
• Smart Retry Logic: Configurable HTTP status codes and custom predicates for retry conditions
• Comprehensive Monitoring: Detailed feedback on retry attempts and exhaustion
• Cancellation Support: Proper handling of cancellation tokens

🔧 Usage Examples

Basic Rate Limiting

var rateLimiter = new TokenBucketRateLimiter(maxRequests: 10, timeWindow: TimeSpan.FromMinutes(1));
var result = await operation.WithRateLimitAsync(rateLimiter);

Retry with Exponential Backoff

var retryPolicy = RetryPolicy.ExponentialBackoff(maxRetries: 3, baseDelay: TimeSpan.FromSeconds(1));
var result = await operation.WithRetryAsync(retryPolicy);

Combined Usage

var result = await apiOperation
    .WithRateLimitAsync(rateLimiter)
    .WithRetryAsync(retryPolicy);

Custom Retry Conditions

var policy = new RetryPolicy
{
    MaxRetries = 5,
    ShouldRetryPredicate = problem => problem.StatusCode == 503 || problem.Detail?.Contains("timeout") == true
};

🧪 Testing

• 40 comprehensive tests covering all scenarios
• Unit tests for individual components
• Integration tests for combined usage
• Edge case coverage including cancellation, timeouts, and error conditions

🔄 Integration

The implementation seamlessly integrates with the existing Result-based error handling and railway-oriented programming patterns. All new functionality follows the library's established conventions and coding standards.

📊 Technical Details

• Thread-safe implementations using proper locking mechanisms
• Async-first design with cancellation token support
• Extension methods for easy integration with existing Result chains
• Configurable logging integration for monitoring and debugging
• Memory-efficient queue management for rate limiting

Fixes #4.

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