feat: 品牌替换 + 启动优化 + AGENTS.md 模板定制

- 品牌替换：OpenCode/opencode → AirCoding/aircoding（16+ 文件）
- Logo ASCII art：修复 left/right 行数不匹配导致的启动崩溃
- 启动诊断：添加 OPENCODE_PRINT_TIMING 计时探针
- dev 模式默认 --pure 跳过外部插件加载
- AGENTS.md 模板：追加 AirCoding 多 Agent 专项段落
- architect prompt + plugin：强化 AGENTS.md 产出验证

packages/opencode/test/server/AGENTS.md

@@ -0,0 +1,15 @@
+# Server Test Guide
+
+Use these patterns for server and HttpApi middleware tests in this directory.
+
+- Prefer focused middleware tests with tiny fake routes over full API route trees when testing routing, context, proxying, or middleware policy.
+- Use `testEffect(...)` with `NodeHttpServer.layerTest` for the primary in-test server and make relative `HttpClient` requests against it.
+- Use tiny `HttpApiBuilder` probe groups that declare the typed middleware under test and expose context such as `WorkspaceRouteContext`, `InstanceRef`, or `WorkspaceRef`.
+- Declare middleware in the same order as production when testing interactions, for example `InstanceContextMiddleware` followed by `WorkspaceRoutingMiddleware`.
+- For secondary upstream servers, build Effect `NodeHttpServer.layer(...)` into the current test scope with `Layer.build(...)` so the listener stays alive until the test scope exits.
+- Avoid `Bun.serve` when testing Effect HTTP middleware. Keep the test in the Effect HTTP stack unless the production path being tested is Bun-specific.
+- For WebSocket paths, use `Socket.makeWebSocket(...)` from the test client and assert protocol forwarding or frame relay when relevant.
+- Use scoped test layers for flags, database reset, and other global mutable state. Restore flags and reset state in finalizers.
+- Use `tmpdirScoped({ git: true })` plus `Project.use.fromDirectory(dir)` for project-backed requests.
+- If a test needs persisted state without matching runtime state, keep direct database setup inside a narrowly named helper that explains that state.
+- Add comments for non-obvious test topology, especially tests involving both the local test server and a fake upstream server.