feat: xiaohe upgrade + 启动器更名 Xiaohe Agent + CLI 输出全英文

- upgrade: 查版本(install.sh)→确认→rich 进度条下载→落 runtime 切 current(留两版)→重装三件套→自动 sync
- launcher: 'Xiaohe Agent.app' / 'Xiaohe Agent.desktop'，自动清理旧 XiaoheAgent.{command,app,desktop}
- 修复 _current_version 对缺失 current 软链误判为 'current'
- 全部提示/log 英文化；93 tests passed

tests/test_sync_workspace.py

@@ -100,19 +100,23 @@ class TestCreateLauncher:
     ) -> None:
         (runtime / "assets" / "icon").mkdir(parents=True)
         (runtime / "assets" / "icon" / "XiaoheAgent.icns").write_bytes(b"icns")
-        legacy = fake_home / "Desktop" / "XiaoheAgent.command"
-        legacy.write_text("#!/bin/sh\n")
+        legacy_cmd = fake_home / "Desktop" / "XiaoheAgent.command"
+        legacy_cmd.write_text("#!/bin/sh\n")
+        legacy_app = fake_home / "Desktop" / "XiaoheAgent.app"
+        legacy_app.mkdir()
         monkeypatch.setattr(
             sync_mod.os, "uname", lambda: type("U", (), {"sysname": "Darwin"})
         )
         sync_mod._create_launcher()
-        app = fake_home / "Desktop" / "XiaoheAgent.app"
+        app = fake_home / "Desktop" / "Xiaohe Agent.app"
         executable = app / "Contents" / "MacOS" / "XiaoheAgent"
-        assert (app / "Contents" / "Info.plist").is_file()
+        plist = (app / "Contents" / "Info.plist").read_text()
+        assert "Xiaohe Agent" in plist
         assert (app / "Contents" / "Resources" / "XiaoheAgent.icns").is_file()
         assert executable.stat().st_mode & 0o111
         assert "xiaohe" in executable.read_text()
-        assert not legacy.exists()  # superseded .command removed
+        assert not legacy_cmd.exists()  # superseded .command removed
+        assert not legacy_app.exists()  # renamed from XiaoheAgent.app
 
     def test_linux_desktop_entry_with_icon(
         self, runtime: Path, fake_home: Path, monkeypatch: pytest.MonkeyPatch
@@ -124,16 +128,8 @@ class TestCreateLauncher:
         )
         sync_mod._create_launcher()
         entry = (
-            fake_home / ".local" / "share" / "applications" / "XiaoheAgent.desktop"
+            fake_home / ".local" / "share" / "applications" / "Xiaohe Agent.desktop"
         )
-        assert "Icon=xiaohe-agent" in entry.read_text()
-        assert (
-            fake_home
-            / ".local"
-            / "share"
-            / "icons"
-            / "hicolor"
-            / "512x512"
-            / "apps"
-            / "xiaohe-agent.png"
-        ).is_file()
+        text = entry.read_text()
+        assert "Name=Xiaohe Agent" in text
+        assert "Icon=xiaohe-agent" in text