`DaemonHost()` returns `http://docker.example.com` for ssh transport

cli/connhelper/connhelper.go の getConnectionHelper と、cli/context/docker/load.go のクライアントホストの処理から始めます。DOCKER_HOST="ssh://user@1.2.3.4" で動作を再現し、DaemonHost() がどのように導出されるかを追跡します。CLI が ssh、unix、pipe を含む実際に設定された transport を公開し、呼び出し元がリモートホストとローカルホストを区別できるようになれば完了です。

Description

cli.DaemonHost() gives http://docker.example.com when docker host is set to ssh

the behavior comes from getConnectionHelper in https://github.com/docker/cli/blob/84038691220e7ba3329a177e4e3357b4ee0e3a52/cli/connhelper/connhelper.go#L64 the Host is set to http://docker.example.com in connection helper and later updated the host attribute in the cli.Client at https://github.com/docker/cli/blob/84038691220e7ba3329a177e4e3357b4ee0e3a52/cli/context/docker/load.go#L115

the daemon host is specially useful in docker compose when we want to know if the docker host it's remote or not, like you are doing here https://github.com/docker/cli/blob/84038691220e7ba3329a177e4e3357b4ee0e3a52/cli/context/docker/load.go#L127

Reproduce

DOCKER_HOST="ssh://user@1.2.3.4" docker 

Expected behavior

we should be able to know whenever the docker cli is accessing the docker host via ssh, unix, pipe, etc

basically we should be able to access docker host used

docker version

Client: Docker Engine - Community
 Version:           28.2.2
 API version:       1.50
 Go version:        go1.24.3
 Git commit:        e6534b4
 Built:             Fri May 30 12:07:26 2025
 OS/Arch:           linux/amd64
 Context:           default

Server: Docker Engine - Community
 Engine:
  Version:          28.2.2
  API version:      1.50 (minimum version 1.24)
  Go version:       go1.24.3
  Git commit:       45873be
  Built:            Fri May 30 12:07:26 2025
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.7.27
  GitCommit:        05044ec0a9a75232cad458027ca83437aae3f4da
 runc:
  Version:          1.2.5
  GitCommit:        v1.2.5-0-g59923ef
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

docker info

Client: Docker Engine - Community
 Version:    28.2.2
 Context:    default
 Debug Mode: false
 Plugins:
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.24.0
    Path:     /usr/libexec/docker/cli-plugins/docker-buildx
  compose: Docker Compose (Docker Inc.)
    Version:  v2.36.2
    Path:     /usr/libexec/docker/cli-plugins/docker-compose

Additional Info

No response