ip link add: support bond device creation

Introduced support `ip link add NAME type bond [OPTIONS]`.
Accepts all bond options identical to iproute2.

Uses netlink-packet-route FromStr/Display for all bond options
(BondMode, BondArpValidate, BondArpAllTargets, BondPrimaryReselect,
BondFailOverMac, BondAdSelect, BondXmitHashPolicy) via a generic
parse_from_str helper.

Added arp_ip_target, ns_ip6_target, ad_actor_sys_prio,
ad_user_port_key, ad_actor_system display fields.

Includes 7 integration tests for bond creation with various
option combinations.

Signed-off-by: Gris Ge <cnfourt@gmail.com>

Author: cathay4t

src/ip/link/add.rs

@@ -52,6 +52,9 @@ impl LinkAddCommand {
             InfoKind::Vlan => {
                 base_conf.apply(base_conf.apply_vlan(&handle).await?)?
             }
+            InfoKind::Bond => {
+                base_conf.apply(base_conf.apply_bond(&handle).await?)?
+            }
             t => {
                 return Err(CliError::from(format!(
                     "Unsupported device type: {t}"