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/tui/test/util/renderer.test.ts

@@ -0,0 +1,30 @@
+import { expect, test } from "bun:test"
+import { destroyRenderer } from "../../src/util/renderer"
+
+test("clears the terminal title before destroying the renderer", () => {
+  const calls: string[] = []
+  destroyRenderer({
+    isDestroyed: false,
+    setTerminalTitle(title) {
+      calls.push(`title:${title}`)
+    },
+    destroy() {
+      calls.push("destroy")
+    },
+  })
+  expect(calls).toEqual(["title:", "destroy"])
+})
+
+test("still clears the title after renderer destruction", () => {
+  const calls: string[] = []
+  destroyRenderer({
+    isDestroyed: true,
+    setTerminalTitle(title) {
+      calls.push(`title:${title}`)
+    },
+    destroy() {
+      calls.push("destroy")
+    },
+  })
+  expect(calls).toEqual(["title:"])
+})