feat: AI 身份改为 zmo + 更新机制指向自有仓库

- 8 个系统提示词 txt 的 "You are opencode/OpenCode" 改为 zmo，问"你是谁"答 zmo
- copilot-gpt-5 的 "Your name is" 同步改 zmo
- 更新机制(installation/index.ts)指向 helpLogin/zmo-cli：
  GitHub release API、install 脚本地址、.zmo/bin 路径检测、userAgent
  使以后发布的新版能更新到自有 zmo 版本，而非被覆盖回 opencode
- zenmux X-Title/Referer 改为 zmo 标识

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

packages/opencode/package.json

@@ -87,8 +87,8 @@
     "@opencode-ai/llm": "workspace:*",
     "@opencode-ai/plugin": "workspace:*",
     "@opencode-ai/script": "workspace:*",
-    "@opencode-ai/server": "workspace:*",
     "@opencode-ai/sdk": "workspace:*",
+    "@opencode-ai/server": "workspace:*",
     "@opencode-ai/ui": "workspace:*",
     "@openrouter/ai-sdk-provider": "2.9.0",
     "@opentelemetry/api": "1.9.0",