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/core/test/plugin/skill.test.ts

@@ -0,0 +1,32 @@
+import { describe, expect } from "bun:test"
+import { Effect, Layer } from "effect"
+import { AgentV2 } from "@opencode-ai/core/agent"
+import { FSUtil } from "@opencode-ai/core/fs-util"
+import { SkillPlugin } from "@opencode-ai/core/plugin/skill"
+import { SkillV2 } from "@opencode-ai/core/skill"
+import { SkillDiscovery } from "@opencode-ai/core/skill/discovery"
+import { testEffect } from "../lib/effect"
+
+const it = testEffect(
+  SkillV2.layer.pipe(
+    Layer.provide(FSUtil.defaultLayer),
+    Layer.provide(SkillDiscovery.defaultLayer),
+    Layer.provideMerge(AgentV2.locationLayer),
+  ),
+)
+
+describe("SkillPlugin.Plugin", () => {
+  it.effect("registers the built-in customize-opencode skill", () =>
+    Effect.gen(function* () {
+      const skill = yield* SkillV2.Service
+      yield* SkillPlugin.Plugin.effect.pipe(Effect.provideService(SkillV2.Service, skill))
+
+      expect(yield* skill.list()).toContainEqual(
+        expect.objectContaining({
+          name: "customize-opencode",
+          description: expect.stringContaining("opencode's own configuration"),
+        }),
+      )
+    }),
+  )
+})