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/editor.test.ts

@@ -0,0 +1,32 @@
+import { afterEach, expect, test } from "bun:test"
+import { normalizePromptContent, openEditor } from "../src/editor"
+
+const editor = process.env.EDITOR
+const visual = process.env.VISUAL
+
+afterEach(() => {
+  process.env.EDITOR = editor
+  process.env.VISUAL = visual
+})
+
+test("rejects when the external editor cannot start", async () => {
+  delete process.env.VISUAL
+  process.env.EDITOR = "opencode-editor-that-does-not-exist"
+  const renderer = {
+    suspend() {},
+    resume() {},
+    requestRender() {},
+    currentRenderBuffer: { clear() {} },
+  }
+
+  await expect(openEditor({ value: "original", renderer: renderer as never })).rejects.toThrow()
+})
+
+test("normalizes a single trailing editor newline for one-line prompts", () => {
+  expect(normalizePromptContent("hello\n")).toBe("hello")
+  expect(normalizePromptContent("hello\r\n")).toBe("hello")
+})
+
+test("preserves multiline prompts that end with a newline", () => {
+  expect(normalizePromptContent("hello\nworld\n")).toBe("hello\nworld\n")
+})