[Lombok K1] Support @Singular annotation

^KT-46959

plugins/lombok/testData/box/builderSingular.kt

@@ -0,0 +1,52 @@
+// WITH_STDLIB
+// FULL_JDK
+// FILE: User.java
+import lombok.Builder;
+import lombok.Data;
+import lombok.Singular;
+
+@Builder
+@Data
+public class User {
+    @Singular private java.util.Map<String, Integer> numbers;
+    @Singular private java.util.List<String> statuses;
+}
+
+// FILE: Other.java
+import lombok.Builder;
+import lombok.Data;
+import lombok.Singular;
+
+@Builder(setterPrefix = "with")
+@Data
+public class Other {
+    @Singular("singleSome") private java.util.List<Integer> some;
+}
+
+// FILE: test.kt
+fun box(): String {
+    val userBuilder = User.builder()
+        .status("wrong")
+        .clearStatuses()
+        .status("hello")
+        .statuses(listOf("world", "!"))
+        .number("1", 1)
+        .numbers(mapOf("2" to 2, "3" to 3))
+
+    val user = userBuilder.build()
+
+    val outer = Other.builder()
+        .withSingleSome(1)
+        .withSome(listOf(2, 3))
+        .build()
+
+    val expectedNumbers = mapOf("1" to 1, "2" to 2, "3" to 3)
+    val expectedStatuses = listOf("hello", "world", "!")
+    val expectedSome = listOf(1, 2, 3)
+
+    return if (user.numbers == expectedNumbers && user.statuses == expectedStatuses && outer.some == expectedSome) {
+        "OK"
+    } else {
+        "Error: $user"
+    }
+}