Add stdlib extension wrapper coverage test

lynglib/src/commonTest/kotlin/net/sergeych/lyng/StdlibExtensionWrapperCoverageTest.kt

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2026 Sergey S. Chernov
+ *
+ * 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 net.sergeych.lyng
+
+import kotlinx.coroutines.test.runTest
+import net.sergeych.lyng.miniast.BuiltinDocRegistry
+import net.sergeych.lyng.stdlib_included.rootLyng
+import kotlin.test.Test
+import kotlin.test.assertTrue
+
+class StdlibExtensionWrapperCoverageTest {
+    @Test
+    fun stdlibExtensionWrappersPresent() = runTest {
+        val src = rootLyng
+        val classNames = LinkedHashSet<String>()
+        val classRe = Regex(
+            "^\\s*(?:(?:abstract|override|closed|private|protected|static|open|extern)\\s+)*(?:fun|val|var)\\s+([A-Za-z_][A-Za-z0-9_]*)\\.",
+            RegexOption.MULTILINE
+        )
+        classRe.findAll(src).forEach { m ->
+            val name = m.groupValues.getOrNull(1)?.trim()
+            if (!name.isNullOrEmpty()) classNames.add(name)
+        }
+
+        val scope = Script.newScope()
+        val missing = mutableListOf<String>()
+        for (className in classNames) {
+            val members = BuiltinDocRegistry.extensionMemberNamesFor(className)
+            for (member in members) {
+                val callable = scope.get(extensionCallableName(className, member))
+                val getter = scope.get(extensionPropertyGetterName(className, member))
+                if (callable == null && getter == null) {
+                    missing += "$className.$member"
+                }
+            }
+        }
+
+        assertTrue(missing.isEmpty(), "Missing stdlib extension wrappers: ${missing.sorted()}")
+    }
+}