fix(frontend): give AmneziaWG the same UDP tag and its own tag color

The Inbounds list only special-cased isWireguard/isHysteria for the "UDP"
network badge, so an AmneziaWG row showed just the bare protocol tag with
no transport badge next to it. Added the missing isAmneziawg flag (mirrors
isWireguard exactly) and wired it into the same branch.

Client-row protocol-color maps in ClientsPage/HostList had no amneziawg
entry, silently falling back to grey -- ClientInfoModal already had
amneziawg: 'yellow' from earlier work, these two just never got it.

frontend/src/pages/hosts/HostList.tsx

@@ -39,6 +39,7 @@ const INBOUND_PROTOCOL_COLORS: Record<string, string> = {
   hysteria: 'cyan',
   hysteria2: 'green',
   wireguard: 'gold',
+  amneziawg: 'yellow',
   http: 'purple',
   mixed: 'lime',
   tunnel: 'orange',