chore: suppress warnings on Windows

[vansangpfiev]

Describe Your Changes

This pull request includes various changes across multiple files to improve code consistency, fix bugs, and enhance compatibility with different platforms. The most important changes include adding support for wide character conversion on Windows, ensuring compatibility with different compilers, and improving type safety.

Platform Compatibility Improvements:

• engine/cli/main.cc: Added #include "utils/widechar_conv.h" and updated directory path handling to use Utf8ToWstring on Windows. [1] [2]
• engine/services/hardware_service.cc: Added conditional compilation for environment variable handling to support _MSC_VER (Microsoft Compiler). [1] [2] [3]
• engine/utils/cortex_utils.h: Updated GetDateRFC1123 function to use gmtime_s on Windows.
• engine/utils/engine_matcher_utils.h: Updated sscanf to sscanf_s on Windows for secure parsing. (F0b0cb26L37R37)

Type Safety Enhancements:

• engine/common/message.h: Changed division result to be cast to uint32_t for created_at.
• engine/utils/hardware/gguf/gguf_file_estimate.h: Updated various calculations to use static_cast for type safety. [1] [2] [3] [4] [5]

Code Consistency:

• engine/config/model_config.h: Removed unnecessary line breaks.
• engine/utils/hardware/gguf/ggml.h: Added 'f' suffix to floating-point literals for consistency. [1] [2]

Bug Fixes:

• engine/services/model_service.cc: Removed unused exception variable in catch blocks. [1] [2]
• engine/utils/command_executor.h: Ensured buffer size is cast to int for fgets.

Other Changes:

• engine/utils/hardware/cpu_info.h: Cast CPU usage to float.
• engine/utils/format_utils.h: Removed unused exception variable in catch block.

Fixes Issues

• Closes #
• Closes #

Self Checklist

• Added relevant comments, esp in complex areas
• Updated docs (for bug fixes / features)
• Created issues for follow-up changes or refactoring needed