This isn't the apheleia rewrite, just a redesign to fix the module's
current issues with its +onsave feature.
+ Rethinks how the formatter dispatches to lsp/eglot's formatter.
+ Stops format-all from being too imposing with its warnings.
+ Relies more on format-all-mode to control formatting-on-save.
+ Sidestep +format-buffer-a hackery when using lsp/eglot formatters.
Fixes#5121Fixes#5128Fixes#5133