refactor: move act under internal

The runner is an application, not a library. `act/model` and
`act/exprparser` were the last packages anything outside this repository
consumed and they now live in actionslib, so nothing needs the rest of
`act` to be importable, and keeping it importable invites the coupling
that was just removed.

Import paths only, the files are unchanged.

Assisted-by: Codet:GPT-5.1-Codex

internal/act/container/docker_auth.go

@@ -0,0 +1,71 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// Copyright 2021 The nektos/act Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+//go:build !(WITHOUT_DOCKER || !(linux || darwin || windows || netbsd))
+
+package container
+
+import (
+	"context"
+
+	"gitea.com/gitea/runner/internal/act/common"
+
+	"github.com/distribution/reference"
+	"github.com/docker/cli/cli/config"
+	"github.com/moby/moby/api/types/registry"
+)
+
+func LoadDockerAuthConfig(ctx context.Context, image string) (registry.AuthConfig, error) {
+	logger := common.Logger(ctx)
+	// config.LoadDefaultConfigFile panics on nil io.Writer when the config
+	// file is malformed; use config.Load to route errors through the logger.
+	cfg, err := config.Load(config.Dir())
+	if err != nil {
+		logger.Warnf("Could not load docker config: %v", err)
+		return registry.AuthConfig{}, err
+	}
+	registryKey := registryAuthConfigKey("docker.io")
+	if image != "" {
+		if registryRef, refErr := reference.ParseNormalizedNamed(image); refErr != nil {
+			logger.Warnf("Could not normalize image reference: %v", refErr)
+		} else {
+			registryKey = registryAuthConfigKey(reference.Domain(registryRef))
+		}
+	}
+
+	authConfig, err := cfg.GetAuthConfig(registryKey)
+	if err != nil {
+		logger.Warnf("Could not get auth config from docker config: %v", err)
+		return registry.AuthConfig{}, err
+	}
+
+	return registry.AuthConfig(authConfig), nil
+}
+
+func LoadDockerAuthConfigs(ctx context.Context) map[string]registry.AuthConfig {
+	logger := common.Logger(ctx)
+	cfg, err := config.Load(config.Dir())
+	if err != nil {
+		logger.Warnf("Could not load docker config: %v", err)
+		return nil
+	}
+	creds, err := cfg.GetAllCredentials()
+	if err != nil {
+		logger.Warnf("Could not get docker auth configs: %v", err)
+		return nil
+	}
+	authConfigs := make(map[string]registry.AuthConfig, len(creds))
+	for k, v := range creds {
+		authConfigs[k] = registry.AuthConfig(v)
+	}
+
+	return authConfigs
+}
+
+func registryAuthConfigKey(domainName string) string {
+	if domainName == "docker.io" || domainName == "index.docker.io" {
+		return "https://index.docker.io/v1/"
+	}
+	return domainName
+}