Function get_needed_components 

pub fn get_needed_components(
    protocol: &WebUiProtocol,
    entry_id: &str,
    inventory_hex: &str,
) -> (Vec<String>, String)

Walk the protocol fragment graph from entry_id and return the names of all components the route needs that are NOT in the client’s inventory.

entry_id is the route’s component name (e.g., "cb-page-group"). inventory is the client’s bitmask of already-loaded components.

Returns (needed_names, updated_inventory_hex).