router: Router.Route consumes NormalizedInput directly (slice 11)

Change Route from (ctx, utterance string, now) to (ctx, input NormalizedInput, now).
The ingress-constructed NormalizedInput now reaches the cascade intact — no
reconstruction downstream. TryFastPath receives the same input, not a rebuilt one.
All callers (production, eval framework, tests) updated to construct NormalizedInput.

cmd/mavend/turnroute.go

@@ -79,7 +79,7 @@ func (r *turnRoute) resolve(ctx context.Context) (router.Decision, bool, *dialog
 			r.err = router.ErrNoIntents
 			return
 		}
-		r.dec, r.err = r.h.router.Route(ctx, r.input.Text, r.now)
+		r.dec, r.err = r.h.router.Route(ctx, r.input, r.now)
 	})
 	return r.dec, r.cont, r.prev, r.err
 }