fix(hyprland): resolve desc: monitor names before generating config

Extract shared resolveMonitorNames to backend package so both
Hyprland and Sway backends resolve desc: prefixed names to actual
connector names before applying monitor layout.

Previously the Hyprland backend wrote desc:... literally into
monitors.conf, which Hyprland ignores, causing monitors to be
positioned incorrectly or not configured at all.

internal/backend/hyprland.go

@@ -93,6 +93,12 @@ func (h *hyprlandBackend) GetMonitors(ctx context.Context) ([]MonitorInfo, error
 // ApplyLayout writes the monitor configuration file and calls hyprctl reload.
 // The config is written atomically (temp file + rename) to prevent corruption.
 func (h *hyprlandBackend) ApplyLayout(ctx context.Context, monitors []MonitorConfig) error {
+	var err error
+	monitors, err = resolveMonitorNames(ctx, monitors, h.GetMonitors, h.logger)
+	if err != nil {
+		return fmt.Errorf("resolve monitor names: %w", err)
+	}
+
 	content := h.generateConf(monitors)
 
 	destPath, err := h.resolveOutputPath()