depend on the published agent-compose proto module

[yorkew-east8]

Summary

Replace the vendored Agent Compose protobuf snapshot with the published Go module github.com/chaitin/agent-compose/proto@v0.1.8.

The remote agent-compose command already talks Connect/protobuf. It no longer needs a local proto copy, buf generation, or import-path remapping. The published proto module is the same contract the daemon and sdk/go already consume.

Changes

• Depend on github.com/chaitin/agent-compose/proto@v0.1.8 in go.mod.
• Point products/agentcompose imports at the published Connect clients and messages.
• Remove products/agentcompose/proto/, products/agentcompose/gen/, scripts/sync-agent-compose-proto.sh, and the task agent-compose:proto:* targets.
• Drop the protoc-gen-go / protoc-gen-connect-go tool dependencies that only served that snapshot.
• Bump connectrpc.com/connect to v1.19.2 and google.golang.org/protobuf to v1.36.12 with the proto module.

Command behavior, flags, and config are unchanged.

Test plan

• task fmt:check
• task lint
• task test
• Local build/install and chaitin-cli agent-compose subcommand smoke

[yorkew-east8]

@monkeyscan 评审下这个 MR

[monkeyscan]

PR Title: depend on the published agent-compose proto module

Commit: a9b444d

整体评估

本次变更把 products/agentcompose 的 protobuf/Connect 依赖从仓库内自带的快照（products/agentcompose/proto 与 gen）切换为已发布模块 github.com/chaitin/agent-compose/proto v0.1.8，并同步删除生成脚本、buf 配置与 protoc 工具依赖，同时升级 connect 与 protobuf；除依赖与 import 外没有其它逻辑改动，方向与 MR 描述一致。

总结

我逐一核对了 16 个 Go 文件的新 import、go.mod/go.sum、Taskfile 与 .github/workflows/ci.yml：导入路径彼此一致且与模块布局（模块路径含 /proto，消息在 agentcompose/v2、health/v1，Connect 客户端在对应 *connect 子包）相符，go.sum 已包含 agent-compose/proto v0.1.8、connect v1.19.2、protobuf v1.36.12 的校验值，CI 与文档也不再引用被删除的 task/脚本；被删除生成代码的调用点（如 newPSCommand、newAgentCommand）均位于本次已修改文件中，未发现残留旧导入。唯一无法在仓库内证实的是 v0.1.8 模块内容与被移除快照提交 85ba5a4 的对应关系（原快照取自未发布分支 feat/cli-logs-event-id-filter），但缺少可证实证据，故不作为问题上报。结论：建议合并，未发现必须修复项。