feat: remove emojis from runner logging, add Starting job container group (#940)

Aligns runner log output more closely with `actions/runner`:

- Strip the whale, rocket, cloud, construction, chequered-flag, and exclamation-mark glyphs from log lines and drop the now-unused `logPrefix` constant.
- Reword `no outputs used step '%s'` → `No outputs registered for step '%s'` (the original was ungrammatical and inaccurate — it fires when `set-output` references an unknown step ID).
- Wrap the docker pull/network/create/start phase of job container startup in a `::group::Starting job container` / `::endgroup::` collapsible section, mirroring `actions/runner`. Since act drives Docker through the SDK rather than the CLI, we can't echo `##[command]/usr/bin/docker create ...` lines verbatim — instead the helper emits a summary inside the group:

  ```
  ::group::Starting job container
  image: <image>
  name: <container-name>
  network: <network-name>
  ::endgroup::
  ```

- Extracted the emit into a `printStartJobContainerGroup` helper (parallel to `printRunActionHeader` in `step_run.go`) and added a golden-style test `TestPrintStartJobContainerGroupGolden`.
- Drive-by: replace two remaining literal `"raw_output"` strings in `run_context.go` with the existing `rawOutputField` constant.

Closes #935

---
This PR was written with the help of Claude Opus 4.7

Reviewed-on: https://gitea.com/gitea/runner/pulls/940
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: silverwind <me@silverwind.io>
Co-committed-by: silverwind <me@silverwind.io>

act/container/docker_build.go

@@ -25,9 +25,9 @@ func NewDockerBuildExecutor(input NewDockerBuildExecutorInput) common.Executor {
 	return func(ctx context.Context) error {
 		logger := common.Logger(ctx)
 		if input.Platform != "" {
-			logger.Infof("%sdocker build -t %s --platform %s %s", logPrefix, input.ImageTag, input.Platform, input.ContextDir)
+			logger.Infof("docker build -t %s --platform %s %s", input.ImageTag, input.Platform, input.ContextDir)
 		} else {
-			logger.Infof("%sdocker build -t %s %s", logPrefix, input.ImageTag, input.ContextDir)
+			logger.Infof("docker build -t %s %s", input.ImageTag, input.ContextDir)
 		}
 		if common.Dryrun(ctx) {
 			return nil

act/container/docker_logger.go

@@ -26,8 +26,6 @@ type dockerMessage struct {
 	Progress string `json:"progress"`
 }
 
-const logPrefix = "  \U0001F433  "
-
 func logDockerResponse(logger logrus.FieldLogger, dockerResponse io.ReadCloser, isError bool) error {
 	if dockerResponse == nil {
 		return nil

act/container/docker_pull.go

@@ -24,7 +24,7 @@ import (
 func NewDockerPullExecutor(input NewDockerPullExecutorInput) common.Executor {
 	return func(ctx context.Context) error {
 		logger := common.Logger(ctx)
-		logger.Debugf("%sdocker pull %v", logPrefix, input.Image)
+		logger.Debugf("docker pull %v", input.Image)
 
 		if common.Dryrun(ctx) {
 			return nil

act/container/docker_run.go

@@ -53,7 +53,7 @@ func NewContainer(input *NewContainerInput) ExecutionsEnvironment {
 
 func (cr *containerReference) ConnectToNetwork(name string) common.Executor {
 	return common.
-		NewDebugExecutor("%sdocker network connect %s %s", logPrefix, name, cr.input.Name).
+		NewDebugExecutor("docker network connect %s %s", name, cr.input.Name).
 		Then(
 			common.NewPipelineExecutor(
 				cr.connect(),
@@ -90,7 +90,7 @@ func supportsContainerImagePlatform(ctx context.Context, cli client.APIClient) b
 
 func (cr *containerReference) Create(capAdd, capDrop []string) common.Executor {
 	return common.
-		NewInfoExecutor("%sdocker create image=%s platform=%s entrypoint=%+q cmd=%+q network=%+q", logPrefix, cr.input.Image, cr.input.Platform, cr.input.Entrypoint, cr.input.Cmd, cr.input.NetworkMode).
+		NewInfoExecutor("docker create image=%s platform=%s entrypoint=%+q cmd=%+q network=%+q", cr.input.Image, cr.input.Platform, cr.input.Entrypoint, cr.input.Cmd, cr.input.NetworkMode).
 		Then(
 			common.NewPipelineExecutor(
 				cr.connect(),
@@ -102,7 +102,7 @@ func (cr *containerReference) Create(capAdd, capDrop []string) common.Executor {
 
 func (cr *containerReference) Start(attach bool) common.Executor {
 	return common.
-		NewInfoExecutor("%sdocker run image=%s platform=%s entrypoint=%+q cmd=%+q network=%+q", logPrefix, cr.input.Image, cr.input.Platform, cr.input.Entrypoint, cr.input.Cmd, cr.input.NetworkMode).
+		NewInfoExecutor("docker run image=%s platform=%s entrypoint=%+q cmd=%+q network=%+q", cr.input.Image, cr.input.Platform, cr.input.Entrypoint, cr.input.Cmd, cr.input.NetworkMode).
 		Then(
 			common.NewPipelineExecutor(
 				cr.connect(),
@@ -125,7 +125,7 @@ func (cr *containerReference) Start(attach bool) common.Executor {
 
 func (cr *containerReference) Pull(forcePull bool) common.Executor {
 	return common.
-		NewInfoExecutor("%sdocker pull image=%s platform=%s username=%s forcePull=%t", logPrefix, cr.input.Image, cr.input.Platform, cr.input.Username, forcePull).
+		NewInfoExecutor("docker pull image=%s platform=%s username=%s forcePull=%t", cr.input.Image, cr.input.Platform, cr.input.Username, forcePull).
 		Then(
 			NewDockerPullExecutor(NewDockerPullExecutorInput{
 				Image:     cr.input.Image,
@@ -147,7 +147,7 @@ func (cr *containerReference) Copy(destPath string, files ...*FileEntry) common.
 
 func (cr *containerReference) CopyDir(destPath, srcPath string, useGitIgnore bool) common.Executor {
 	return common.NewPipelineExecutor(
-		common.NewInfoExecutor("%sdocker cp src=%s dst=%s", logPrefix, srcPath, destPath),
+		common.NewInfoExecutor("docker cp src=%s dst=%s", srcPath, destPath),
 		cr.copyDir(destPath, srcPath, useGitIgnore),
 		func(ctx context.Context) error {
 			// If this fails, then folders have wrong permissions on non root container
@@ -177,7 +177,7 @@ func (cr *containerReference) UpdateFromImageEnv(env *map[string]string) common.
 
 func (cr *containerReference) Exec(command []string, env map[string]string, user, workdir string) common.Executor {
 	return common.NewPipelineExecutor(
-		common.NewInfoExecutor("%sdocker exec cmd=[%s] user=%s workdir=%s", logPrefix, strings.Join(command, " "), user, workdir),
+		common.NewInfoExecutor("docker exec cmd=[%s] user=%s workdir=%s", strings.Join(command, " "), user, workdir),
 		cr.connect(),
 		cr.find(),
 		cr.exec(command, env, user, workdir),

act/container/docker_volume.go

@@ -42,7 +42,7 @@ func NewDockerVolumeRemoveExecutor(volumeName string, force bool) common.Executo
 func removeExecutor(volume string, force bool) common.Executor {
 	return func(ctx context.Context) error {
 		logger := common.Logger(ctx)
-		logger.Debugf("%sdocker volume rm %s", logPrefix, volume)
+		logger.Debugf("docker volume rm %s", volume)
 
 		if common.Dryrun(ctx) {
 			return nil