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/pty/info-schema.test.ts

@@ -0,0 +1,27 @@
+import { describe, expect, test } from "bun:test"
+import { Schema } from "effect"
+import { Pty } from "@opencode-ai/core/pty"
+
+const sample = (pid: number) => ({
+  id: "pty_01J5Y5H0AH4Q4NXJ6P4C3P5V2K",
+  title: "demo",
+  command: "cmd.exe",
+  args: [],
+  cwd: "C:\\",
+  status: "running",
+  pid,
+})
+
+describe("Pty.Info", () => {
+  test("accepts pid 0 (Windows ConPTY assigns the pid asynchronously)", () => {
+    expect(Schema.decodeUnknownSync(Pty.Info)(sample(0)).pid).toBe(0)
+  })
+
+  test("accepts a positive pid", () => {
+    expect(Schema.decodeUnknownSync(Pty.Info)(sample(48012)).pid).toBe(48012)
+  })
+
+  test("rejects a negative pid", () => {
+    expect(() => Schema.decodeUnknownSync(Pty.Info)(sample(-1))).toThrow()
+  })
+})