Function handle_inlay_hints 

pub async fn handle_inlay_hints(
    state: Arc<ServerState>,
    params: InlayHintParams,
    config: &InlayHintsConfig,
    client: Client,
    full_config: Arc<RwLock<DepsConfig>>,
) -> Vec<InlayHint>

Handles inlay hint requests using trait-based delegation.

Returns version status hints for all registry dependencies in the document. Gracefully degrades by returning empty vec on any errors.