mavend: read a spoken correction of the previous turn (V-455)

CorrectMisroute has been in the router since it was written with no caller
outside a test. repair.go is the half that reads the words: a marker saying
she was wrong plus the intent it should have been, with the negated half
skipped, and it teaches the classifier and redoes the request under the
corrected intent.

docs/design.md

@@ -223,6 +223,23 @@ Not alternatives — layers:
 Router contract: `[{"intent":<enum>, key?, value?, text?, verb?}, ...]` over
 7 intents (`fact, reminder, note, query, act, chat, system`).
 
+#### Saying she got it wrong is a feature
+
+Landed 2026-08-04 (Vikunja #455). `Router.CorrectMisroute` could always append a
+corrected utterance as a new classifier example, and until now nothing in the
+daemon called it, so the mechanism existed and the behaviour did not.
+
+`cmd/mavend/repair.go` reaches it. He says she got it wrong and names what it
+should have been — "нет, это заметка", "это не напоминание, а факт" — and three
+things happen in one turn: the classifier learns the utterance under the named
+intent, the request is redone under it, and she says the correction landed. The
+utterance he is correcting TO is the one with no "не" in front of it.
+
+Read before routing, next to the confirm and clarify turns, because a correction
+routed as a fresh utterance files the correction itself. One turn is correctable
+once, inside five minutes, and only turns she acted on — a clarify asked instead
+of acting, so there is nothing yet to be wrong about.
+
 #### A restart expires a parked question
 
 Decided 2026-08-04 (Vikunja #385). The follow-up dialogue session survives a