Fix: mutateKwArg was appending not overwriting args

e2e/playwright/sketch-tests.spec.ts

@@ -262,7 +262,7 @@ test.describe('Sketch tests', () => {
 
       await expect(page.getByTestId('segment-overlay')).toHaveCount(2)
 
-      // drag startProfieAt handle
+      // drag startProfileAt handle
       await page.mouse.move(startPX[0], startPX[1])
       await page.mouse.down()
       await page.mouse.move(startPX[0] + dragPX, startPX[1] - dragPX, step5)

src/lang/modifyAst.ts

@@ -212,12 +212,13 @@ export function mutateKwArg(
   node: CallExpressionKw,
   val: Expr
 ): boolean {
-  node.arguments.forEach((arg, i) => {
+  for (let i = 0; i < node.arguments.length; i++) {
+    const arg = node.arguments[i]
     if (arg.label.name === label) {
       node.arguments[i].arg = val
       return true
     }
-  })
+  }
   node.arguments.push(createLabeledArg(label, val))
   return false
 }