fix(outbound): preserve custom headers for HTTP outbounds (#5519)

The Outbounds form routed HTTP through the SOCKS-shared simpleAuth adapter, which only knew address/port/user/pass, so xray's top-level settings.headers was dropped on both load and save. Opening and re-saving an HTTP outbound destroyed its headers.

Add headers to the HTTP wire/form schemas, round-trip it via dedicated httpFromWire/httpToWire helpers, and expose a HeaderMapEditor in the form. Only settings-level headers round-trip; xray-core ignores per-server headers.

frontend/src/schemas/forms/outbound-form.ts

@@ -80,6 +80,7 @@ export const HttpOutboundFormSettingsSchema = z.object({
   port: PortSchema.default(8080),
   user: z.string().default(''),
   pass: z.string().default(''),
+  headers: z.record(z.string(), z.string()).default({}),
 });
 export type HttpOutboundFormSettings = z.infer<typeof HttpOutboundFormSettingsSchema>;
 

frontend/src/schemas/protocols/outbound/http.ts

@@ -21,5 +21,6 @@ export type HttpOutboundServer = z.infer<typeof HttpOutboundServerSchema>;
 
 export const HttpOutboundSettingsSchema = z.object({
   servers: z.array(HttpOutboundServerSchema).min(1),
+  headers: z.record(z.string(), z.string()).optional(),
 });
 export type HttpOutboundSettings = z.infer<typeof HttpOutboundSettingsSchema>;