Fix index out of bounds for items call in SelectableLazyColumn

foundation/src/main/kotlin/org/jetbrains/jewel/foundation/lazy/SelectableLazyColumn.kt

@@ -125,7 +125,7 @@ fun SelectableLazyColumn(
 
                 is Entry.Items -> items(
                     count = entry.count,
-                    key = { entry.key(entry.startIndex + it) },
+                    key = { entry.key(it) },
                     contentType = { entry.contentType(it) },
                 ) { index ->
                     val itemScope = SelectableLazyItemScope(entry.key(index) in state.selectedKeys, isFocused)

foundation/src/test/kotlin/org/jetbrains/jewel/foundation/lazy/SelectableLazyColumnTest.kt

@@ -0,0 +1,56 @@
+package org.jetbrains.jewel.foundation.lazy
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.requiredHeight
+import androidx.compose.foundation.lazy.LazyListState
+import androidx.compose.foundation.text.BasicText
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.testTag
+import androidx.compose.ui.test.junit4.createComposeRule
+import androidx.compose.ui.test.onNodeWithTag
+import androidx.compose.ui.unit.dp
+import kotlinx.coroutines.runBlocking
+import org.junit.Rule
+import org.junit.Test
+
+internal class SelectableLazyColumnTest {
+
+    @get:Rule
+    val composeRule = createComposeRule()
+
+    @Test
+    fun `column with multiple items`() = runBlocking<Unit> {
+        val items1 = (0..10).toList()
+        val items2 = (11..50).toList()
+        val scrollState = SelectableLazyListState(LazyListState())
+        composeRule.setContent {
+            Box(modifier = Modifier.requiredHeight(100.dp)) {
+                SelectableLazyColumn(state = scrollState) {
+                    items(
+                        items1.size,
+                        key = {
+                            items1[it]
+                        },
+                    ) {
+                        val itemText = "Item ${items1[it]}"
+                        BasicText(itemText, modifier = Modifier.testTag(itemText))
+                    }
+
+                    items(
+                        items2.size,
+                        key = {
+                            items2[it]
+                        },
+                    ) {
+                        val itemText = "Item ${items2[it]}"
+                        BasicText(itemText, modifier = Modifier.testTag(itemText))
+                    }
+                }
+            }
+        }
+        composeRule.awaitIdle()
+        composeRule.onNodeWithTag("Item 20").assertDoesNotExist()
+        scrollState.scrollToItem(20)
+        composeRule.onNodeWithTag("Item 20").assertExists()
+    }
+}