fix(sockopt): rename interfaceName to interface so xray honors it

xray-core reads the bind-interface sockopt as json:"interface", but the schema and forms used interfaceName. Go's JSON unmarshal is case-insensitive, yet interfacename != interface, so the value never reached xray and interface binding silently did nothing. Rename the field across the schema, the inbound/outbound forms, and the golden fixture to match xray-core and the official docs.

frontend/src/schemas/protocols/stream/sockopt.ts

@@ -65,7 +65,7 @@ export const SockoptStreamSettingsSchema = z.object({
   tcpcongestion: TcpCongestionSchema.default('bbr'),
   V6Only: z.boolean().default(false),
   tcpWindowClamp: z.number().int().min(0).default(600),
-  interfaceName: z.string().default(''),
+  interface: z.string().default(''),
   trustedXForwardedFor: z.array(z.string()).default([]),
   addressPortStrategy: AddressPortStrategySchema.default('none'),
   happyEyeballs: HappyEyeballsSchema.optional(),