fix(server): preserve v1 auth compatibility

packages/server/src/auth.ts

@@ -13,11 +13,12 @@ export type DecodedCredentials = {
 
 export type Info = {
   readonly password: Option.Option<string>
+  readonly username: string
 }
 
 export class Config extends Context.Service<Config, Info>()("@opencode/ServerAuthConfig") {
-  static configLayer(input: Info) {
-    return Layer.succeed(this, this.of(input))
+  static configLayer(input: Pick<Info, "password">) {
+    return Layer.succeed(this, this.of({ ...input, username: "opencode" }))
   }
 
   static get layer() {
@@ -32,7 +33,7 @@ export function required(config: Info) {
 export function authorized(credentials: DecodedCredentials, config: Info) {
   return (
     Option.isSome(config.password) &&
-    credentials.username === "opencode" &&
+    credentials.username === config.username &&
     Redacted.value(credentials.password) === config.password.value
   )
 }

packages/server/src/process.ts

@@ -148,7 +148,7 @@ function dispatch(
   application: Ref.Ref<Option.Option<App>>,
   shutdown: Deferred.Deferred<void>,
 ): App {
-  const auth = ServerAuth.Config.of({ password: Option.some(password) })
+  const auth = ServerAuth.Config.of({ password: Option.some(password), username: "opencode" })
   return Effect.gen(function* () {
     const request = yield* HttpServerRequest.HttpServerRequest
     const url = new URL(request.url, "http://localhost")

packages/server/test/auth.test.ts

@@ -3,7 +3,7 @@ import { ServerAuth } from "@opencode-ai/server/auth"
 import { Option, Redacted } from "effect"
 
 test("accepts only the fixed opencode username", () => {
-  const config = { password: Option.some("secret") }
+  const config = { password: Option.some("secret"), username: "opencode" }
   expect(ServerAuth.authorized({ username: "opencode", password: Redacted.make("secret") }, config)).toBe(true)
   expect(ServerAuth.authorized({ username: "custom", password: Redacted.make("secret") }, config)).toBe(false)
 })