docs: clarify relationship between different features

With klogr being deprecated there might be some confusion whether
textlogger or klog.Background should be used instead.

klog.go

@@ -14,9 +14,26 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Package klog implements logging analogous to the Google-internal C++ INFO/ERROR/V setup.
-// It provides functions Info, Warning, Error, Fatal, plus formatting variants such as
-// Infof. It also provides V-style logging controlled by the -v and -vmodule=file=2 flags.
+// Package klog contains the following functionality:
+//
+//   - output routing as defined via command line flags ([InitFlags])
+//   - log formatting as text, either with a single, unstructured string ([Info], [Infof], etc.)
+//     or as a structured log entry with message and key/value pairs ([InfoS], etc.)
+//   - management of a go-logr [Logger] ([SetLogger], [Background], [TODO])
+//   - helper function for logging values ([Format]) and managing the state of klog ([CaptureState], [State.Restore])
+//   - wrappers for [logr] APIs for contextual logging where the wrappers can
+//     be turned into no-ops ([EnableContextualLogging], [NewContext], [FromContext],
+//     [LoggerWithValues], [LoggerWithName]); if the ability to turn of
+//     contextual logging is not needed, then go-logr can also be used directly
+//   - type aliases for go-logr types to simplify imports in code which uses both (e.g. [Logger])
+//   - [k8s.io/klog/v2/textlogger]: a logger which uses the same formatting as klog log with
+//     simpler output routing; beware that it comes with its own command line flags
+//     and does not use the ones from klog
+//   - [k8s.io/klog/v2/ktesting]: per-test output in Go unit tests
+//   - [k8s.io/klog/v2/klogr]: a deprecated, standalone [logr.Logger] on top of the main klog package;
+//     use [Background] instead if klog output routing is needed, [k8s.io/klog/v2/textlogger] if not
+//   - [k8s.io/klog/v2/examples]: demos of this functionality
+//   - [k8s.io/klog/v2/test]: reusable tests for [logr.Logger] implementations
 //
 // Basic examples:
 //

textlogger/textlogger.go

@@ -15,8 +15,10 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-// Package textlogger contains an implementation of the logr interface
-// which is producing the exact same output as klog.
+// Package textlogger contains an implementation of the logr interface which is
+// producing the exact same output as klog. It does not route output through
+// klog (i.e. ignores [k8s.io/klog/v2.InitFlags]). Instead, all settings must be
+// configured through its own [NewConfig] and [Config.AddFlags].
 package textlogger
 
 import (