refactor: ♻️ ach package accepts its configuration as a parameter rather than reading from global config

pkg/metrics/example_test.go

@@ -0,0 +1,64 @@
+package metrics_test
+
+import (
+	"fmt"
+
+	"github.com/bitechdev/ResolveSpec/pkg/metrics"
+)
+
+// ExampleNewPrometheusProvider_default demonstrates using default configuration
+func ExampleNewPrometheusProvider_default() {
+	// Initialize with default configuration
+	provider := metrics.NewPrometheusProvider(nil)
+	metrics.SetProvider(provider)
+
+	fmt.Println("Provider initialized with defaults")
+	// Output: Provider initialized with defaults
+}
+
+// ExampleNewPrometheusProvider_custom demonstrates using custom configuration
+func ExampleNewPrometheusProvider_custom() {
+	// Create custom configuration
+	config := &metrics.Config{
+		Enabled:            true,
+		Provider:           "prometheus",
+		Namespace:          "myapp",
+		HTTPRequestBuckets: []float64{0.01, 0.05, 0.1, 0.5, 1, 2, 5},
+		DBQueryBuckets:     []float64{0.001, 0.01, 0.05, 0.1, 0.5, 1},
+	}
+
+	// Initialize with custom configuration
+	provider := metrics.NewPrometheusProvider(config)
+	metrics.SetProvider(provider)
+
+	fmt.Println("Provider initialized with custom config")
+	// Output: Provider initialized with custom config
+}
+
+// ExampleDefaultConfig demonstrates getting default configuration
+func ExampleDefaultConfig() {
+	config := metrics.DefaultConfig()
+	fmt.Printf("Default provider: %s\n", config.Provider)
+	fmt.Printf("Default enabled: %v\n", config.Enabled)
+	// Output:
+	// Default provider: prometheus
+	// Default enabled: true
+}
+
+// ExampleConfig_ApplyDefaults demonstrates applying defaults to partial config
+func ExampleConfig_ApplyDefaults() {
+	// Create partial configuration
+	config := &metrics.Config{
+		Namespace: "myapp",
+		// Other fields will be filled with defaults
+	}
+
+	// Apply defaults
+	config.ApplyDefaults()
+
+	fmt.Printf("Provider: %s\n", config.Provider)
+	fmt.Printf("Namespace: %s\n", config.Namespace)
+	// Output:
+	// Provider: prometheus
+	// Namespace: myapp
+}