Add ability to open KCL samples in-app (#3912)

* Add a shell script to get the list of KCL samples into the app

* Add support for overwriting current file with sample

* Move these KCL commands down into FileMachineProvider

* Add support for creating a new file on desktop

* Make it so these files aren't set to "renaming mode" right away

* Add support for initializing default values that are functions

* Add E2E tests

* Add a code menu item to load a sample

* Fix tsc issues

* Remove `yarn fetch:samples` from `yarn postinstall`

* Remove change to arg initialization logic, I was holding it wrong

* Switch to use new manifest file from kcl-samples repo

* Update tests now that we use proper sample titles

* Remove double-load from units menu test

* @jtran feedback

* Don't encode `https://` that's silly

* fmt

* Update e2e/playwright/testing-samples-loading.spec.ts

Co-authored-by: Kurt Hutten <k.hutten@protonmail.ch>

* Test feedback

* Add a test step to actually check the file contents were written to (@Irev-Dev feedback)

---------

Co-authored-by: Kurt Hutten <k.hutten@protonmail.ch>

src/components/CommandBar/CommandBarSelectionInput.tsx

@@ -31,8 +31,8 @@ function getSemanticSelectionType(selectionType: Array<Selection['type']>) {
   return Array.from(semanticSelectionType)
 }
 
-const selectionSelector = (snapshot: StateFrom<typeof modelingMachine>) =>
-  snapshot.context.selectionRanges
+const selectionSelector = (snapshot?: StateFrom<typeof modelingMachine>) =>
+  snapshot?.context.selectionRanges
 
 function CommandBarSelectionInput({
   arg,
@@ -49,7 +49,7 @@ function CommandBarSelectionInput({
   const [hasSubmitted, setHasSubmitted] = useState(false)
   const selection = useSelector(arg.machineActor, selectionSelector)
   const selectionsByType = useMemo(() => {
-    const selectionRangeEnd = selection.codeBasedSelections[0]?.range[1]
+    const selectionRangeEnd = selection?.codeBasedSelections[0]?.range[1]
     return !selectionRangeEnd || selectionRangeEnd === code.length
       ? 'none'
       : getSelectionType(selection)