fix(tools): update golangci-lint to v2 import path (#567)

golangci-lint v2 changed its module path from:
  github.com/golangci/golangci-lint/cmd/golangci-lint
to:
  github.com/golangci/golangci-lint/v2/cmd/golangci-lint

Update both definition sites (DefaultConfig and commonTools map) and
the two test cases that hardcode the v1 path.

Co-authored-by: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

Author: jlec

cmd/tools/install_tools_test.go

@@ -151,7 +151,7 @@ func TestExtractToolNames(t *testing.T) {
 		},
 		{
 			name:     "package without version",
-			packages: []string{"github.com/golangci/golangci-lint/cmd/golangci-lint"},
+			packages: []string{"github.com/golangci/golangci-lint/v2/cmd/golangci-lint"},
 			expected: []string{"golangci-lint"},
 		},
 	}
@@ -233,7 +233,7 @@ func TestExtractToolName_ComplexPaths(t *testing.T) {
 			expected:    "gopls",
 		},
 		{
-			packagePath: "github.com/golangci/golangci-lint/cmd/golangci-lint@latest",
+			packagePath: "github.com/golangci/golangci-lint/v2/cmd/golangci-lint@latest",
 			expected:    "golangci-lint",
 		},
 		{

internal/tools/tools.go

@@ -90,7 +90,7 @@ func DefaultConfig() *Config {
 			},
 			{
 				Name:           "golangci-lint",
-				Package:        "github.com/golangci/golangci-lint/cmd/golangci-lint",
+				Package:        "github.com/golangci/golangci-lint/v2/cmd/golangci-lint",
 				Version:        "@latest",
 				Binary:         "golangci-lint",
 				UpdateStrategy: "auto", // Use stable versions

internal/tools/utils.go

@@ -15,7 +15,7 @@ var commonTools = map[string]string{
 	"gotestsum":     "gotest.tools/gotestsum",
 	"gopls":         "golang.org/x/tools/gopls",
 	"goimports":     "golang.org/x/tools/cmd/goimports",
-	"golangci-lint": "github.com/golangci/golangci-lint/cmd/golangci-lint",
+	"golangci-lint": "github.com/golangci/golangci-lint/v2/cmd/golangci-lint",
 	"staticcheck":   "honnef.co/go/tools/cmd/staticcheck",
 	"dlv":           "github.com/go-delve/delve/cmd/dlv",
 	"gofumpt":       "mvdan.cc/gofumpt",