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/fixture/workspace.ts

@@ -0,0 +1,30 @@
+import { FetchHttpClient } from "effect/unstable/http"
+import { Layer } from "effect"
+import { Database } from "@opencode-ai/core/database/database"
+import { FSUtil } from "@opencode-ai/core/fs-util"
+import { Auth } from "../../src/auth"
+import { Workspace } from "../../src/control-plane/workspace"
+import { RuntimeFlags } from "../../src/effect/runtime-flags"
+import { InstanceBootstrap } from "../../src/project/bootstrap"
+import { InstanceStore } from "../../src/project/instance-store"
+import { Project } from "../../src/project/project"
+import { Vcs } from "../../src/project/vcs"
+import { Session } from "../../src/session/session"
+import { SessionPrompt } from "../../src/session/prompt"
+import { EventV2Bridge } from "../../src/event-v2-bridge"
+
+export const workspaceLayerWithRuntimeFlags = (overrides: Partial<RuntimeFlags.Info>) =>
+  Workspace.layer.pipe(
+    Layer.provide(Auth.defaultLayer),
+    Layer.provide(Session.defaultLayer),
+    Layer.provide(SessionPrompt.defaultLayer),
+    Layer.provide(Project.defaultLayer),
+    Layer.provide(Vcs.defaultLayer),
+    Layer.provide(Database.defaultLayer),
+    Layer.provide(EventV2Bridge.defaultLayer),
+    Layer.provide(FetchHttpClient.layer),
+    Layer.provide(FSUtil.defaultLayer),
+    Layer.provide(RuntimeFlags.layer(overrides)),
+    Layer.provide(InstanceStore.defaultLayer),
+    Layer.provide(InstanceBootstrap.defaultLayer),
+  )