feat: add slog logging (#432)

* feat(op): user slog for logging

integrate with golang.org/x/exp/slog for logging.
provide a middleware for request scoped logging.

BREAKING CHANGES:

1. OpenIDProvider and sub-interfaces get a Logger()
method to return the configured logger;
2. AuthRequestError now takes the complete Authorizer,
instead of only the encoder. So that it may use its Logger() method.
3. RequestError now takes a Logger as argument.

* use zitadel/logging

* finish op and testing
without middleware for now

* minimum go version 1.19

* update go mod

* log value testing only on go 1.20 or later

* finish the RP and example

* ping logging release

pkg/oidc/error_go120_test.go

@@ -0,0 +1,83 @@
+//go:build go1.20
+
+package oidc
+
+import (
+	"io"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"golang.org/x/exp/slog"
+)
+
+func TestError_LogValue(t *testing.T) {
+	type fields struct {
+		Parent           error
+		ErrorType        errorType
+		Description      string
+		State            string
+		redirectDisabled bool
+	}
+	tests := []struct {
+		name   string
+		fields fields
+		want   slog.Value
+	}{
+		{
+			name: "parent",
+			fields: fields{
+				Parent: io.EOF,
+			},
+			want: slog.GroupValue(slog.Any("parent", io.EOF)),
+		},
+		{
+			name: "description",
+			fields: fields{
+				Description: "oops",
+			},
+			want: slog.GroupValue(slog.String("description", "oops")),
+		},
+		{
+			name: "errorType",
+			fields: fields{
+				ErrorType: ExpiredToken,
+			},
+			want: slog.GroupValue(slog.String("type", string(ExpiredToken))),
+		},
+		{
+			name: "state",
+			fields: fields{
+				State: "123",
+			},
+			want: slog.GroupValue(slog.String("state", "123")),
+		},
+		{
+			name: "all fields",
+			fields: fields{
+				Parent:      io.EOF,
+				Description: "oops",
+				ErrorType:   ExpiredToken,
+				State:       "123",
+			},
+			want: slog.GroupValue(
+				slog.Any("parent", io.EOF),
+				slog.String("description", "oops"),
+				slog.String("type", string(ExpiredToken)),
+				slog.String("state", "123"),
+			),
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			e := &Error{
+				Parent:           tt.fields.Parent,
+				ErrorType:        tt.fields.ErrorType,
+				Description:      tt.fields.Description,
+				State:            tt.fields.State,
+				redirectDisabled: tt.fields.redirectDisabled,
+			}
+			got := e.LogValue()
+			assert.Equal(t, tt.want, got)
+		})
+	}
+}