[1.x] Move translation files from src/ to the root/lang directory

[mra9994]

Summary

Moved translation files from src/ to the root lang/ directory.

Reason

• src/ is reserved for PSR-4 autoloadable PHP code and should contain only classes/interfaces.
• Composer scans this directory based on PSR-4 autoloading.
• Translation files are not PSR-4 PHP classes; they are language resources (arrays).
• To follow Laravel conventions and keep a clear separation between source code and resources, translations were moved to the lang/ directory.

Testing

• All tests were executed successfully.

[milwad-dev]

Thanks!