* Create a new shared `SplitMenu` component.
* Refactor the pdf compile button & detached compile button:
- Rename `detach-compile-button` to `detach-compile-button-wrapper`
- Rename `pdf-compile-button-inner` to `detach-compile-button`
- Move some of the logic from `detach-compile-button-wrapper` to `detach-compile-button`
- Create a new `compile-button.less` to centralize all of the compile button (detached/non-detached) custom styles rule.
- Extract the animated striped CSS definition to the dedicated CSS file, change the class from `btn-recompile-group-has-changes` to `btn-striped-animated`
- Refactor other className(s) appropriately according to the new component name
- Delete the unused `changes-to-autocompile` css rule since it has not been used anywhere
* Implement the new pdf compile button with the new `SplitMenu` component.
GitOrigin-RevId: d1d055bffd311923fc47b4681605ce8ba8e26f25