Use a 1:1 mapping of netbird client to netbird account

- Add debug endpoint for monitoring netbird clients
- Add types package with AccountID type
- Refactor netbird roundtrip to key clients by AccountID
- Multiple domains can share the same client per account
- Add status notifier for tunnel connection updates
- Add OIDC flags to CLI
- Add tests for netbird client management

proxy/server_test.go

@@ -0,0 +1,48 @@
+package proxy
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDebugEndpointDisabledByDefault(t *testing.T) {
+	s := &Server{}
+	assert.False(t, s.DebugEndpointEnabled, "debug endpoint should be disabled by default")
+}
+
+func TestDebugEndpointAddr(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "empty defaults to localhost",
+			input:    "",
+			expected: "localhost:8444",
+		},
+		{
+			name:     "explicit localhost preserved",
+			input:    "localhost:9999",
+			expected: "localhost:9999",
+		},
+		{
+			name:     "explicit address preserved",
+			input:    "0.0.0.0:8444",
+			expected: "0.0.0.0:8444",
+		},
+		{
+			name:     "127.0.0.1 preserved",
+			input:    "127.0.0.1:8444",
+			expected: "127.0.0.1:8444",
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			result := debugEndpointAddr(tc.input)
+			assert.Equal(t, tc.expected, result)
+		})
+	}
+}