style: add missing newline at end of files

[keyserfaty]

Summary

Adds missing newline characters at the end of two JavaScript files to comply with POSIX standards and common coding conventions. This ensures all text files end with a newline character, which helps avoid issues with certain tools and version control systems.

Changes

• Added newline at end of src/modules/config/selectors.js
• Added newline at end of src/utils/libs/vfs_fonts.js

Testing

No functional changes were made. To verify:

• Run existing test suite to ensure no regressions
• Check that linters/formatters pass without warnings about missing newlines
• Confirm files now end with proper newline characters using cat -e or similar tools