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/opencode/test/session/session-schema.test.ts

@@ -0,0 +1,78 @@
+import { describe, expect, test } from "bun:test"
+import { Schema } from "effect"
+import { ProjectV2 } from "@opencode-ai/core/project"
+import { MessageID, SessionID } from "../../src/session/schema"
+import { Session } from "../../src/session/session"
+
+const info = {
+  id: SessionID.descending(),
+  slug: "test-session",
+  projectID: ProjectV2.ID.global,
+  workspaceID: undefined,
+  directory: "/tmp/opencode",
+  parentID: undefined,
+  summary: undefined,
+  cost: 0,
+  tokens: { input: 0, output: 0, reasoning: 0, cache: { read: 0, write: 0 } },
+  share: undefined,
+  title: "Test session",
+  version: "1.0.0",
+  time: {
+    created: 1,
+    updated: 2,
+    compacting: undefined,
+    archived: undefined,
+  },
+  permission: undefined,
+  revert: undefined,
+} satisfies Session.Info
+
+describe("Session schema", () => {
+  test("encodes undefined optional session fields as omitted keys", () => {
+    const encoded = Schema.encodeUnknownSync(Session.Info)(info) as Record<string, unknown>
+
+    for (const key of ["workspaceID", "parentID", "summary", "share", "permission", "revert"]) {
+      expect(Object.hasOwn(encoded, key)).toBe(false)
+    }
+    expect(Object.hasOwn(encoded.time as Record<string, unknown>, "compacting")).toBe(false)
+    expect(Object.hasOwn(encoded.time as Record<string, unknown>, "archived")).toBe(false)
+    expect(JSON.stringify(encoded)).not.toContain("parentID")
+  })
+
+  test("encodes undefined optional global session project fields as omitted keys", () => {
+    const encoded = Schema.encodeUnknownSync(Session.GlobalInfo)({
+      ...info,
+      project: {
+        id: ProjectV2.ID.global,
+        name: undefined,
+        worktree: "/tmp/opencode",
+      },
+    }) as Record<string, unknown>
+
+    expect(Object.hasOwn(encoded, "parentID")).toBe(false)
+    expect(Object.hasOwn(encoded.project as Record<string, unknown>, "name")).toBe(false)
+  })
+
+  test("encodes nested undefined optional session fields as omitted keys", () => {
+    const encoded = Schema.encodeUnknownSync(Session.Info)({
+      ...info,
+      summary: {
+        additions: 1,
+        deletions: 2,
+        files: 3,
+        diffs: undefined,
+      },
+      revert: {
+        messageID: MessageID.ascending(),
+        partID: undefined,
+        snapshot: undefined,
+        diff: undefined,
+      },
+    }) as Record<string, unknown>
+
+    expect(Object.hasOwn(encoded.summary as Record<string, unknown>, "diffs")).toBe(false)
+    for (const key of ["partID", "snapshot", "diff"]) {
+      expect(Object.hasOwn(encoded.revert as Record<string, unknown>, key)).toBe(false)
+    }
+  })
+})