This commit explicitly splits raw fir builder in lazy mode on AST and stubs. By default, in tests we have an AST tree loaded, so all our `disallowTreeLoading` is useless in unit tests mode ^KT-64646 Fixed ^KT-64898 ^KT-64899 ^KT-64900 ^KT-64901
^KT-60327 fixed Merge-request: KT-MR-13221 Merged-by: Egor Kulikov <Egor.Kulikov@jetbrains.com>