Merge gitea/act into act/

Merges the `gitea.com/gitea/act` fork into this repository as the `act/`
directory and consumes it as a local package. The `replace github.com/nektos/act
=> gitea.com/gitea/act` directive is removed; act's dependencies are merged
into the root `go.mod`.

- Imports rewritten: `github.com/nektos/act/pkg/...` → `gitea.com/gitea/act_runner/act/...`
  (flattened — `pkg/` boundary dropped to match the layout forgejo-runner adopted).
- Dropped act's CLI (`cmd/`, `main.go`) and all upstream project files; kept
  the library tree + `LICENSE`.
- Added `// Copyright <year> The Gitea Authors ...` / `// Copyright <year> nektos`
  headers to 104 `.go` files.
- Pre-existing act lint violations annotated inline with
  `//nolint:<linter> // pre-existing issue from nektos/act`.
  `.golangci.yml` is unchanged vs `main`.
- Makefile test target: `-race -short` (matches forgejo-runner).
- Pre-existing integration test failures fixed: race in parallel executor
  (atomic counters); TestSetupEnv / command_test / expression_test /
  run_context_test updated to match gitea fork runtime; TestJobExecutor and
  TestActionCache gated on `testing.Short()`.

Full `gitea/act` commit history is reachable via the second parent.

Co-Authored-By: Claude (Opus 4.7) <noreply@anthropic.com>

act/container/docker_volume.go

@@ -0,0 +1,59 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// Copyright 2020 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/act_runner/act/common"
+
+	"github.com/docker/docker/api/types/filters"
+	"github.com/docker/docker/api/types/volume"
+)
+
+func NewDockerVolumeRemoveExecutor(volumeName string, force bool) common.Executor {
+	return func(ctx context.Context) error {
+		cli, err := GetDockerClient(ctx)
+		if err != nil {
+			return err
+		}
+		defer cli.Close()
+
+		list, err := cli.VolumeList(ctx, volume.ListOptions{Filters: filters.NewArgs()})
+		if err != nil {
+			return err
+		}
+
+		for _, vol := range list.Volumes {
+			if vol.Name == volumeName {
+				return removeExecutor(volumeName, force)(ctx)
+			}
+		}
+
+		// Volume not found - do nothing
+		return nil
+	}
+}
+
+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)
+
+		if common.Dryrun(ctx) {
+			return nil
+		}
+
+		cli, err := GetDockerClient(ctx)
+		if err != nil {
+			return err
+		}
+		defer cli.Close()
+
+		return cli.VolumeRemove(ctx, volume, force)
+	}
+}