add receiver to cell lambda, and appropriate DslMarker annotations

Author: sproctor

data-table/src/commonMain/kotlin/com/seanproctor/datatable/BasicDataTable.kt

@@ -99,11 +99,11 @@ fun BasicDataTable(
                     }
                     check(cells.size <= columns.size) { "Row $rowIndex has too many cells." }
                     check(cells.size >= columns.size) { "Row $rowIndex doesn't have enough cells." }
-                    cells.forEach { cellData ->
+                    cells.forEachIndexed { index, cellData ->
                         // Must have exactly 1 Composable per cell
                         Box(Modifier.padding(contentPadding)) {
                             cellContentProvider.RowCellContent {
-                                cellData()
+                                cellData(TableCellScopeImpl(index))
                             }
                         }
                     }

data-table/src/commonMain/kotlin/com/seanproctor/datatable/DataTableDsl.kt

@@ -4,6 +4,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.unit.Dp
 
+@Target(AnnotationTarget.CLASS, AnnotationTarget.TYPE)
 @DslMarker
 annotation class DataTableScopeMarker
 
@@ -17,7 +18,7 @@ interface DataTableScope {
      * Creates a new row in the [BasicDataTable] with the specified content.
      */
     fun row(
-        content: TableRowScope.() -> Unit
+        content: @DataTableScopeMarker TableRowScope.() -> Unit
     )
 }
 
@@ -29,7 +30,12 @@ interface TableRowScope {
     var isFooter: Boolean
     var backgroundColor: Color
 
-    fun cell(content: @Composable () -> Unit)
+    fun cell(content: @DataTableScopeMarker @Composable TableCellScope.() -> Unit)
+}
+
+@DataTableScopeMarker
+interface TableCellScope {
+    val columnIndex: Int
 }
 
 internal class DataTableScopeImpl(
@@ -56,13 +62,17 @@ internal class TableRowScopeImpl(
     override var isHeader: Boolean = false
     override var isFooter: Boolean = false
     override var backgroundColor: Color = Color.Unspecified
-    val cells = mutableListOf<@Composable () -> Unit>()
+    val cells = mutableListOf<@Composable TableCellScope.() -> Unit>()
 
     init {
         apply(content)
     }
 
-    override fun cell(content: @Composable () -> Unit) {
+    override fun cell(content: @Composable TableCellScope.() -> Unit) {
         cells += content
     }
 }
+
+internal class TableCellScopeImpl(
+    override val columnIndex: Int,
+) : TableCellScope