KCL: Make shell stdlib fn use keyword arguments (#5293)

Before:

```
shell({ faces = ['end'], thickness = caseThickness }, case)
```

After:
```
shell(case, faces = ['end'], thickness = caseThickness)
```

src/wasm-lib/tests/executor/inputs/fillet-and-shell.kcl

@@ -75,7 +75,7 @@ m25Screw(border + rpizWidth / 2 + widthBetweenScrews / 2, 0 + border + rpizLengt
 
 m25Screw(border + rpizWidth / 2 + widthBetweenScrews / 2, 0 + border + rpizLength / 2 - (lengthBetweenScrews / 2), screwHeight)
 
-shell({
-  faces: ['end'],
-  thickness: caseThickness
-}, case)
+shell(
+  faces = ['end'],
+  thickness = caseThickness
+)