Function resolve_install_files 

pub fn resolve_install_files(
    name: &str,
    source: &Source,
) -> Result<PackageFileInfo, String>

What: Determine new and changed files introduced by installing or upgrading a package.

Inputs:

• name: Package name examined.
• source: Source repository information for remote lookups.

Output:

• Returns a populated PackageFileInfo or an error when file lists cannot be retrieved.

Errors

• Returns Err when remote file list retrieval fails (see get_remote_file_list)
• Returns Err when installed file list retrieval fails (see get_installed_file_list)

Details:

• Compares remote file listings with locally installed files and predicts potential .pacnew creations.