fix: 修正 logo 中 N 和 G 字母造型

N 添加对角线笔画（█▄ █），G 添加内横杠（█ ▀█），
避免与 O 字母造型雷同。同步更新 ui.ts 中的硬编码 wordmark。

packages/core/test/fixture/effect-flock-worker.ts

@@ -0,0 +1,60 @@
+import fs from "fs/promises"
+import os from "os"
+import { Effect, Layer } from "effect"
+import { FSUtil } from "@opencode-ai/core/fs-util"
+import { EffectFlock } from "@opencode-ai/core/util/effect-flock"
+import { Global } from "@opencode-ai/core/global"
+
+type Msg = {
+  key: string
+  dir: string
+  holdMs?: number
+  ready?: string
+  active?: string
+  done?: string
+}
+
+function sleep(ms: number) {
+  return new Promise<void>((resolve) => setTimeout(resolve, ms))
+}
+
+const msg: Msg = JSON.parse(process.argv[2])
+
+const testGlobal = Global.layerWith({
+  home: os.homedir(),
+  data: os.tmpdir(),
+  cache: os.tmpdir(),
+  config: os.tmpdir(),
+  state: os.tmpdir(),
+  bin: os.tmpdir(),
+  log: os.tmpdir(),
+})
+
+const testLayer = EffectFlock.layer.pipe(Layer.provide(testGlobal), Layer.provide(FSUtil.defaultLayer))
+
+async function job() {
+  if (msg.ready) await fs.writeFile(msg.ready, String(process.pid))
+  if (msg.active) await fs.writeFile(msg.active, String(process.pid), { flag: "wx" })
+
+  try {
+    if (msg.holdMs && msg.holdMs > 0) await sleep(msg.holdMs)
+    if (msg.done) await fs.appendFile(msg.done, "1\n")
+  } finally {
+    if (msg.active) await fs.rm(msg.active, { force: true })
+  }
+}
+
+await Effect.runPromise(
+  Effect.gen(function* () {
+    const flock = yield* EffectFlock.Service
+    yield* flock.withLock(
+      Effect.promise(() => job()),
+      msg.key,
+      msg.dir,
+    )
+  }).pipe(Effect.provide(testLayer)),
+).catch((err) => {
+  const text = err instanceof Error ? (err.stack ?? err.message) : String(err)
+  process.stderr.write(text)
+  process.exit(1)
+})