Function load_script_plugins_from_directories 

pub fn load_script_plugins_from_directories<P>(
    directories: &[P],
    compiled_symbols: &[CompiledPluginSymbol],
    filters: &FilterRegistry,
) -> Result<ScriptPluginLibrary, PixelFlowError>
where
    P: AsRef<Path>,

Loads .pf script plugin files from directories into a validated library.