feat(inbounds): TUN adapter type and auto-system options

xray-core 26.9 added three TUN settings the inbound form could not set:

- desc, the tunnel type a new Wintun adapter is created with on Windows.
  The settings schema did not list it, so the parse stripped it and a
  value entered as JSON vanished on the next save;
- autoSystemDnsToGateway (Linux), which points systemd-resolved at the
  TUN gateway;
- autoSystemWfpBlockLeak (Windows), whose dns / misconfigtun filters keep
  traffic from leaking past the TUN.

The tooltips name the platform each one acts on and what it needs, since
the core refuses to build or start the TUN otherwise.

frontend/src/schemas/protocols/inbound/tun.ts

@@ -2,6 +2,8 @@ import { z } from 'zod';
 
 export const TunInboundSettingsSchema = z.object({
   name: z.string().default('xray0'),
+  // Windows: the tunnel type a new Wintun adapter is created with (core default Wintun).
+  desc: z.string().optional(),
   mtu: z.number().int().min(0).default(1500),
   gateway: z.array(z.string()).default([]),
   dns: z.array(z.string()).default([]),