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/op/mock/authorizer.mock.go

@@ -11,6 +11,7 @@ import (
 	gomock "github.com/golang/mock/gomock"
 	http "github.com/zitadel/oidc/v3/pkg/http"
 	op "github.com/zitadel/oidc/v3/pkg/op"
+	slog "golang.org/x/exp/slog"
 )
 
 // MockAuthorizer is a mock of Authorizer interface.
@@ -92,6 +93,20 @@ func (mr *MockAuthorizerMockRecorder) IDTokenHintVerifier(arg0 interface{}) *gom
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "IDTokenHintVerifier", reflect.TypeOf((*MockAuthorizer)(nil).IDTokenHintVerifier), arg0)
 }
 
+// Logger mocks base method.
+func (m *MockAuthorizer) Logger() *slog.Logger {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "Logger")
+	ret0, _ := ret[0].(*slog.Logger)
+	return ret0
+}
+
+// Logger indicates an expected call of Logger.
+func (mr *MockAuthorizerMockRecorder) Logger() *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Logger", reflect.TypeOf((*MockAuthorizer)(nil).Logger))
+}
+
 // RequestObjectSupported mocks base method.
 func (m *MockAuthorizer) RequestObjectSupported() bool {
 	m.ctrl.T.Helper()