Initial release: Go Jdenticon library v0.1.0

- Core library with SVG and PNG generation
- CLI tool with generate and batch commands
- Cross-platform path handling for Windows compatibility
- Comprehensive test suite with integration tests

internal/perfsuite/regression_test.go

@@ -0,0 +1,43 @@
+//go:build perf
+
+package perfsuite_test
+
+import (
+	"os"
+	"testing"
+
+	"github.com/ungluedlabs/go-jdenticon/internal/perfsuite"
+)
+
+// TestPerformanceRegressionSuite can be called from a regular Go test
+func TestPerformanceRegressionSuite(t *testing.T) {
+	if testing.Short() {
+		t.Skip("Skipping performance regression tests in short mode")
+	}
+
+	suite := perfsuite.NewPerformanceSuite()
+	suite.FailOnRegress = false // Don't fail tests, just report
+
+	// Check if we should establish baselines
+	if os.Getenv("ESTABLISH_BASELINES") == "true" {
+		if err := suite.EstablishBaselines(); err != nil {
+			t.Fatalf("Failed to establish baselines: %v", err)
+		}
+		return
+	}
+
+	// Run regression check
+	if err := suite.CheckForRegressions(); err != nil {
+		t.Logf("Performance regression check completed with issues: %v", err)
+		// Don't fail the test, just log the results
+	}
+}
+
+// BenchmarkPerformanceSuite runs all performance benchmarks for standard Go bench testing
+func BenchmarkPerformanceSuite(b *testing.B) {
+	suite := perfsuite.NewPerformanceSuite()
+
+	for _, bench := range suite.Benchmarks {
+		b.Run(bench.Name, bench.BenchmarkFunc)
+	}
+}