fix(i18n/zh): cleanups to Chinese translations (#1341)

- Skills: titles use "Skills（技能）", inline uses "skills" following Anthropic official Chinese translations
- MCP: keep as protocol name, never translate to 应用
- Apps (where EN says "Apps"): 应用
- Commands: 命令, Plugins: 插件, Sessions: 会话
- Remove 571 incorrect CJK-Latin spaces
- Standardize 沙盒→沙箱, 您→你, 仪表盘→主页
- Fix 2 MCP keys incorrectly changed to 应用
- Update header comment with terminology glossary

Author: johnnyshields