…tion

- Comprehensive error_codes.h with logger-specific error codes
- All public APIs now return result_void or result<T>
- All writer interfaces and implementations updated
- Support for both thread_system and standalone modes
- Logger library successfully builds with Result pattern

Implementation highlights:
- add_writer(), start(), stop() return result_void
- get_current_metrics() returns result<performance_metrics>
- All writer write() and flush() methods return result_void
- Proper error propagation throughout the codebase
- Error handling in file operations, network writes, encryption

This completes F2 of Phase 1, establishing robust error handling
throughout the logger system using the Result pattern from thread_system.

Implement interface segregation principle for better modularity:
- Add separate interfaces for writers, filters, formatters, and sinks
- Create unified log_entry structure for data passing
- Update base classes to implement new interfaces
- Add formatter implementations (plain, json, compact)
- Maintain backward compatibility with existing APIs

This change improves component independence and testability while
preserving existing functionality. All tests passing successfully.

- Created logger_config.h with comprehensive validation logic
  - Validates buffer size, batch size, flush interval
  - Validates queue settings, file settings, network settings
  - Validates writer settings, thread count, feature combinations
- Implemented logger_builder with fluent interface
  - Builder pattern for constructing logger instances
  - Automatic configuration validation before build
  - Support for predefined templates
- Added predefined configuration templates
  - production: optimized for production environments
  - debug: immediate output for debugging
  - high_performance: maximized throughput
  - low_latency: minimized latency
- Created comprehensive unit tests
  - 18 tests covering all validation scenarios
  - Tests for builder pattern functionality
  - Tests for invalid configurations
- Updated error_codes.h with make_error helper functions

- Updated README.md with new features and usage examples
  - Added builder pattern examples
  - Documented configuration templates
  - Added error handling examples
  - Documented interface architecture
- Created comprehensive API_REFERENCE.md
  - Complete API documentation for all classes
  - Detailed method signatures and parameters
  - Error codes and handling
  - Migration guide from v1.0
- Updated CHANGELOG.md with Phase 1 changes
  - Documented all F1-F4 improvements
  - Listed all new features and changes
  - Added technical details

…to MinGW/MSYS2

- Upgraded all workflows from deprecated upload-artifact@v3 to v4
- Applied comprehensive improvements to Windows MinGW workflow:
  * Added vcpkg binary caching with x-gha
  * Implemented proper cache key structure with vcpkg commit tracking
  * Added fallback mechanism to system libraries
  * Configured VCPKG_DEFAULT_TRIPLET for x64-mingw-dynamic
- Applied same improvements to Windows MSYS2 workflow
- Updated README_WORKFLOW_IMPROVEMENTS.md to reflect all completed tasks
- All workflows now have consistent caching strategy and resilience

- Created vcpkg.json with required dependencies (fmt, spdlog, gtest, benchmark)
- Fixed .gitignore to not exclude vcpkg.json (removed *.json pattern)
- This fixes all CI/CD workflow failures due to missing vcpkg manifest

- Added missing container headers (unordered_map, vector, deque, queue)
- Added missing concurrency headers (thread, atomic, mutex, condition_variable)
- Added missing utility headers (regex, functional, memory, cstdint)
- Added missing algorithm and character manipulation headers (cctype, algorithm)
- Ensures explicit dependencies for all standard library features used
- Improves portability across different compilers and platforms

- Added template version of make_logger_error for result<T> types
- Fixed type conversion errors in logger.cpp by explicitly specifying template parameters
- Fixed unused private field warning by using type_ field in encrypt_data method
- Added encryption type check to support 'none' encryption mode

- Added Windows socket headers (winsock2.h, ws2tcpip.h) with conditional compilation
- Added Winsock initialization/cleanup for Windows in network_writer and log_server
- Fixed socket API differences between Windows and Unix (closesocket, SD_BOTH, etc.)
- Added 'none' value to encryption_type enum for passthrough mode
- Ensured cross-platform compatibility for network components

  - Update metrics_demo.cpp to use .value() for successful result access
  - Update security_demo.cpp to use .value() for successful result access
  - Ensure proper error handling with result pattern throughout samples

  - Fix API consistency issues
    * Standardize result<T> and result_void usage patterns
    * Add make_logger_error helper functions
    * Support both USE_THREAD_SYSTEM and standalone modes

  - Update sample applications
    * Correct result<T>.value() access patterns
    * Proper error handling in metrics and security demos

- Enhanced CompilerChecks.cmake with Windows-specific configuration
  - Added automatic CI environment detection (ENV{CI}, ENV{GITHUB_ACTIONS})
  - Set CMAKE_TRY_COMPILE_TARGET_TYPE to STATIC_LIBRARY for Windows
  - Added proper MSVC flags: /std:c++20 /permissive- /Zc:__cplusplus /EHsc
  - Added MinGW flags: -std=c++20 -pthread -lstdc++fs -lwinpthread
  - Added check_cpp_stdlib_features() for thread_system compatibility
  - Included C++17 feature checks (optional, variant, string_view)

- Fixed missing headers in writer implementations
  - Added <ctime> to file_writer.cpp and rotating_file_writer.cpp
  - Added <cerrno> to network_writer.cpp for error handling

- Updated all Windows workflows for better C++ feature detection
  - build-windows-vs.yaml: Added MSVC-specific compile flags
  - build-windows-mingw.yaml: Added MinGW threading and filesystem flags
  - build-windows-msys2.yaml: Added MSYS2 compatibility flags

This resolves compilation errors during CMake feature detection phase
on Windows CI runners without requiring workflow file workarounds.\

Fixed platform-specific compilation issues in Windows CI:

1. structured_logger.h:
   - Added Windows-specific includes for Winsock2 and process.h
   - Fixed gethostname() availability on Windows (requires Winsock)
   - Added WSAStartup initialization for Windows in constructor
   - Used _getpid() instead of getpid() on Windows
   - Added fallback hostname handling for Windows

2. network_writer.cpp:
   - Fixed ssize_t type not defined on Windows
   - Added typedef for ssize_t using SSIZE_T on Windows
   - Used int type for send() return value on Windows (MSVC)
   - Added proper type casting for data.length() on Windows

These changes resolve:
- MSYS2: 'gethostname' was not declared in this scope
- Visual Studio: 'ssize_t': undeclared identifier

- Added missing <chrono> header to log_server.h for std::chrono::system_clock types
- Added ssize_t typedef in log_server.cpp for Windows compatibility (recv return type)
- Added ws2_32 library linking for Windows builds to resolve Winsock undefined references

These fixes address Visual Studio compilation errors and MSYS2 linking errors
reported in the Windows CI builds.