Use golangci-lint fmt to format code (#163)

Use `golangci-lint fmt` to format code, upgrading `.golangci.yml` to v2 and mirroring the linter configuration used by https://github.com/go-gitea/gitea. `gci` now handles import ordering into standard, project-local, blank, and default groups.

Mirrors https://github.com/go-gitea/gitea/pull/37194.

Changes:
- Upgrade `.golangci.yml` to v2 format with the same linter set as gitea (minus `prealloc`, `unparam`, `testifylint`, `nilnil` which produced too many pre-existing issues)
- Add path-based exclusions (`bodyclose`, `gosec` in tests; `gosec:G115`/`G117` globally)
- Run lint via `make lint-go` in CI instead of `golangci/golangci-lint-action`, matching the pattern used by other Gitea repos
- Apply safe auto-fixes (`modernize`, `perfsprint`, `usetesting`, etc.)
- Add explanations to existing `//nolint` directives
- Remove dead code (unused `newRemoteReusableWorkflow` and `networkName`), duplicate imports, and shadowed `max` builtins
- Replace deprecated `docker/distribution/reference` with `distribution/reference`
- Fix `Deprecated:` comment casing and simplify nil/len checks

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

Reviewed-on: https://gitea.com/gitea/act/pulls/163
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: silverwind <me@silverwind.io>
Co-committed-by: silverwind <me@silverwind.io>

pkg/container/docker_cli_test.go

@@ -6,7 +6,7 @@
 // See DOCKER_LICENSE for the full license text.
 //
 
-//nolint:unparam,whitespace,depguard,dupl,gocritic
+//nolint:unparam,depguard,gocritic // verbatim copy from docker/cli tests
 package container
 
 import (
@@ -135,7 +135,6 @@ func TestParseRunAttach(t *testing.T) {
 		},
 	}
 	for _, tc := range tests {
-		tc := tc
 		t.Run(tc.input, func(t *testing.T) {
 			config, _ := mustParse(t, tc.input)
 			assert.Equal(t, config.AttachStdin, tc.expected.AttachStdin)
@@ -191,9 +190,8 @@ func TestParseRunWithInvalidArgs(t *testing.T) {
 	}
 }
 
-//nolint:gocyclo
+//nolint:gocyclo // function handles many cases
 func TestParseWithVolumes(t *testing.T) {
-
 	// A single volume
 	arr, tryit := setupPlatformVolume([]string{`/tmp`}, []string{`c:\tmp`})
 	if config, hostConfig := mustParse(t, tryit); hostConfig.Binds != nil {
@@ -261,14 +259,13 @@ func TestParseWithVolumes(t *testing.T) {
 			t.Fatalf("Error parsing %s. Should have a single bind mount and no volumes", arr[0])
 		}
 	}
-
 }
 
 // setupPlatformVolume takes two arrays of volume specs - a Unix style
 // spec and a Windows style spec. Depending on the platform being unit tested,
 // it returns one of them, along with a volume string that would be passed
 // on the docker CLI (e.g. -v /bar -v /foo).
-func setupPlatformVolume(u []string, w []string) ([]string, string) {
+func setupPlatformVolume(u, w []string) ([]string, string) {
 	var a []string
 	if runtime.GOOS == "windows" {
 		a = w
@@ -340,7 +337,7 @@ func TestParseHostname(t *testing.T) {
 	hostnameWithDomain := "--hostname=hostname.domainname"
 	hostnameWithDomainTld := "--hostname=hostname.domainname.tld"
 	for hostname, expectedHostname := range validHostnames {
-		if config, _ := mustParse(t, fmt.Sprintf("--hostname=%s", hostname)); config.Hostname != expectedHostname {
+		if config, _ := mustParse(t, "--hostname="+hostname); config.Hostname != expectedHostname {
 			t.Fatalf("Expected the config to have 'hostname' as %q, got %q", expectedHostname, config.Hostname)
 		}
 	}
@@ -462,7 +459,6 @@ func TestParseDevice(t *testing.T) {
 			t.Fatalf("Expected %v, got %v", deviceMapping, hostconfig.Devices)
 		}
 	}
-
 }
 
 func TestParseNetworkConfig(t *testing.T) {
@@ -634,7 +630,7 @@ func TestParseModes(t *testing.T) {
 	}
 
 	// uts ko
-	_, _, _, err = parseRun([]string{"--uts=container:", "img", "cmd"}) //nolint:dogsled
+	_, _, _, err = parseRun([]string{"--uts=container:", "img", "cmd"}) //nolint:dogsled // ignoring multiple returns in test helpers
 	assert.ErrorContains(t, err, "--uts: invalid UTS mode")
 
 	// uts ok
@@ -678,7 +674,7 @@ func TestParseRestartPolicy(t *testing.T) {
 		},
 	}
 	for restart, expectedError := range invalids {
-		if _, _, _, err := parseRun([]string{fmt.Sprintf("--restart=%s", restart), "img", "cmd"}); err == nil || err.Error() != expectedError {
+		if _, _, _, err := parseRun([]string{"--restart=" + restart, "img", "cmd"}); err == nil || err.Error() != expectedError {
 			t.Fatalf("Expected an error with message '%v' for %v, got %v", expectedError, restart, err)
 		}
 	}
@@ -695,7 +691,7 @@ func TestParseRestartPolicy(t *testing.T) {
 
 func TestParseRestartPolicyAutoRemove(t *testing.T) {
 	expected := "Conflicting options: --restart and --rm"
-	_, _, _, err := parseRun([]string{"--rm", "--restart=always", "img", "cmd"}) //nolint:dogsled
+	_, _, _, err := parseRun([]string{"--rm", "--restart=always", "img", "cmd"}) //nolint:dogsled // ignoring multiple returns in test helpers
 	if err == nil || err.Error() != expected {
 		t.Fatalf("Expected error %v, but got none", expected)
 	}
@@ -967,7 +963,6 @@ func TestConvertToStandardNotation(t *testing.T) {
 
 	for key, ports := range valid {
 		convertedPorts, err := convertToStandardNotation(ports)
-
 		if err != nil {
 			assert.NilError(t, err)
 		}