Remove building scene, add code execution loading indicator to bottom-right controls (#3691)

* Remove isFirstRender because isExecuting means the same and remove building scene

* add small makefile util

* Remove waiting for building scene prompt

* Add a new model state indicator

* fmt lint tsc

---------

Co-authored-by: Frank Noirot <frank@kittycad.io>

e2e/playwright/projects.spec.ts

@@ -495,10 +495,6 @@ test(
 
     await file.click()
 
-    await expect(page.getByTestId('loading')).toBeAttached()
-    await expect(page.getByTestId('loading')).not.toBeAttached({
-      timeout: 20_000,
-    })
     await expect(u.codeLocator).toContainText(
       'A mounting bracket for the Focusrite Scarlett Solo audio interface'
     )