chore: add an annotation to record deprecation meta data

The annotation `@DeprecationInfo` makes it possible to record since when
a `@Deprecated` annotation is in place and what needs to be considered
before removing the affected code.

Extending `@Deprecated` to record this information wasn't possible as
the class is not open.

Author: languitar

kotlin-utils/src/commonMain/kotlin/org/modelix/kotlin/utils/DeprecationInfo.kt

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2023.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.modelix.kotlin.utils
+
+/**
+ * Stores information on [Deprecated] code. This information is intended to facilitate performing the deprecation cycle.
+ *
+ * @property since an information since when the construct is deprecated. Preferably, use an ISO 8601 data such as
+ *                 2022-01-09
+ * @property removalHint an optional hint on when it is ok to remove the deprecated code. For instance, this property
+ *                       can include known uses of the deprecated construct that have to be checked before removing the
+ *                       deprecated code.
+ */
+// The target list is copied from @Deprecated to ensure this annotation is usable in the same places.
+@Target(
+    AnnotationTarget.CLASS,
+    AnnotationTarget.FUNCTION,
+    AnnotationTarget.PROPERTY,
+    AnnotationTarget.ANNOTATION_CLASS,
+    AnnotationTarget.CONSTRUCTOR,
+    AnnotationTarget.PROPERTY_SETTER,
+    AnnotationTarget.PROPERTY_GETTER,
+    AnnotationTarget.TYPEALIAS,
+)
+// This is just metadata to be read by developers. No need for bloating the binary code with this information.
+@Retention(AnnotationRetention.SOURCE)
+annotation class DeprecationInfo(
+    val since: String,
+    val removalHint: String = "",
+)