Improve path conversions and add new string utilities

[narknon]

Description
This PR enhances the string and path conversion utilities in the Helpers library with proper UTF-8 and UTF-16 support. The main improvements include rewriting the path conversion logic to handle Unicode correctly and adding several new utility functions for common string/path operations.

The key motivation is to ensure consistent and correct handling of Unicode paths across different platforms.

Necessary to be merged prior to #884

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Is/requires documentation update

How has this been tested?
Conversion tests/tested with updated lua system.

Checklist

• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• I have added the necessary description of this PR to the changelog, and I have followed the same format as other entries.

Additional context
Breaking Change: The to_charT_string_path() function now returns UTF-8 encoded strings when the target type is char, instead of using locale-dependent encoding. This ensures consistent behavior across platforms but may affect code that relied on the previous locale-specific behavior, but I doubt there is any code that did.

New Functions Added:
ensure_str_as() - Allows explicit target character type conversion
to_utf8_string() - Convenient UTF-8 string conversion
normalize_path_for_lua() - Converts paths to UTF-8 with forward slashes for Lua compatibility
utf8_to_wpath() - Converts UTF-8 paths to Windows wide strings for API compatibility

[github-actions]

Build Details

Name	Information
PR Commit	61ee57e
Merge Commit	40e2bd5
Size	47.81 MB
Last Updated	Jun 9, 25, 8:06:28 PM UTC
Expires At	Jun 23, 25, 8:06:23 PM UTC

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Build Details

Name	Information
PR Commit	61ee57e
Merge Commit	40e2bd5
Size	29.41 MB
Last Updated	Jun 9, 25, 8:09:35 PM UTC
Expires At	Jun 23, 25, 8:09:32 PM UTC