feat(wireguard): client config UX, collapsible config card, configurable DNS

Land the WireGuard client-config UX work on main (the upstream PR #5642
branch could not be pushed to).

- Reusable collapsible ConfigBlock (copy/download/QR, actions aligned right)
  for the client .conf, used by client info and the public sub page.
- Correct .conf: canonical PresharedKey casing and DNS sourced from the inbound
  (configurable per-inbound, default 1.1.1.1, 1.0.0.1).
- Configurable per-inbound DNS for WireGuard (schema + form + backend hint via
  InboundOption.WgDns); inert at the Xray layer.
- Public sub page now shows the WireGuard config, rebuilt from the share link;
  the Go wireguard:// link carries dns/presharedkey/keepalive for completeness.
- QR enabled for the wireguard:// link; link rows are compact like other protocols.
- Client information order is subscription, copy URL, WireGuard config; the
  redundant config tab is removed from the add/edit client modal.
- Drop the Inbound Information and QR Code row actions for WireGuard inbounds.

frontend/src/pages/inbounds/qr/QrCodeModal.tsx

@@ -35,6 +35,7 @@ interface QrItem {
   header: string;
   value: string;
   downloadName?: string;
+  showQr?: boolean;
 }
 
 export default function QrCodeModal({
@@ -122,7 +123,7 @@ export default function QrCodeModal({
         downloadName: `peer-${idx + 1}.conf`,
       });
       if (wireguardLinks[idx]) {
-        items.push({ key: `wl${idx}`, header: `Peer ${idx + 1} link`, value: wireguardLinks[idx] });
+        items.push({ key: `wl${idx}`, header: `Peer ${idx + 1} link`, value: wireguardLinks[idx], showQr: false });
       }
     });
     return items;
@@ -137,7 +138,7 @@ export default function QrCodeModal({
           value={item.value}
           remark={item.header}
           downloadName={item.downloadName || ''}
-          showQr={!isPostQuantumLink(item.value)}
+          showQr={item.showQr !== false && !isPostQuantumLink(item.value)}
         />
       ),
     })),