Introduce error recovery mechanisms with retry logic and circuit breaker integration.

- Added `ErrorRecovery.cc` and `ErrorRecovery.h` for retry and circuit breaker implementations.
- Enhanced swap file handling with transient error retries and exponential backoff (e.g., ENOSPC, EDQUOT).
- Integrated circuit breaker into SwapManager to gracefully handle repeated failures, prevent system overload, and enable automatic recovery.
- Updated `DEVELOPER_GUIDE.md` with comprehensive documentation on error recovery patterns and graceful degradation strategies.
- Refined fsync, temp file creation, and swap file logic with retry-on-failure mechanisms for improved resilience.

Swap.h

@@ -15,6 +15,7 @@
 #include <atomic>
 
 #include "SwapRecorder.h"
+#include "ErrorRecovery.h"
 
 class Buffer;
 
@@ -245,5 +246,8 @@ private:
 	// Error tracking (protected by mtx_)
 	std::deque<SwapError> errors_; // bounded to max 100 entries
 	std::size_t total_error_count_{0};
+
+	// Circuit breaker for swap operations (protected by mtx_)
+	CircuitBreaker circuit_breaker_;
 };
 } // namespace kte