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/Dockerfile

@@ -0,0 +1,18 @@
+FROM alpine AS base
+
+# Disable the runtime transpiler cache by default inside Docker containers.
+# On ephemeral containers, the cache is not useful
+ARG BUN_RUNTIME_TRANSPILER_CACHE_PATH=0
+ENV BUN_RUNTIME_TRANSPILER_CACHE_PATH=${BUN_RUNTIME_TRANSPILER_CACHE_PATH}
+RUN apk add libgcc libstdc++ ripgrep
+
+FROM base AS build-amd64
+COPY dist/opencode-linux-x64-baseline-musl/bin/opencode /usr/local/bin/opencode
+
+FROM base AS build-arm64
+COPY dist/opencode-linux-arm64-musl/bin/opencode /usr/local/bin/opencode
+
+ARG TARGETARCH
+FROM build-${TARGETARCH}
+RUN opencode --version
+ENTRYPOINT ["opencode"]