Function detect_enabled_repos 

pub fn detect_enabled_repos() -> Vec<String>

What: Discover repositories enabled in /etc/pacman.conf.

Inputs:

• None: Reads the system pacman configuration.

Output:

• Repository names in declaration order (e.g., ["core", "extra", "multilib", "chaotic-aur"]).
• The default list (core, extra, multilib) when the file cannot be read.

Details:

• Parses [section] headers, skipping [options], and follows top-level Include = directives one level deep (with simple * glob support) so repos declared in included files are found too.
• Purely local file parsing; never invokes pacman or the network.