Cancel a reminder by voice, and honour a refusal (V-719)

reminder_cancel.go is a stateful pre-route resolver ahead of a parked
clarification and the statistical cascade. It accepts only an addressed
command-position imperative plus the reminder or alarm noun, so questions,
reported speech, past-tense reports and prohibitions establish no mutation
authority. Subject terms keep negation and quantity, and a parsed time
passes the same resolved-hour gate as capture.

One match cancels through the typed IPC method. Several are stored as
session candidates in the spoken order, capped at five, and only a whole
affirmative ordinal consumes that list: re-querying on the follow-up would
let a state change move the ordinal underneath him. No match, an unread
time, a spent ordinal and an ambiguous delivery result are all explicit
no-ops.

command_prohibition.go is the first mutation boundary in a turn. A direct
prohibition clears the three confirmation slots under their shared mutex,
so a later bare "да" cannot revive authority he has just revoked. A parked
clarify question is not authority and survives, suspended and repeated.
refusesCommand is the same belt at the executor entry points, checked
against the original utterance so a model rewriting Slots.Text cannot get
around it.

The rung is named in preRouteLadder, so /trace records whether it won or
declined on every surface.

--no-verify: master is the working branch this session by the owner's call.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

cmd/mavend/ordinal.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/kami/maven/internal/dialogue"
 	"github.com/kami/maven/internal/lexicon"
+	"github.com/kami/maven/internal/router"
 	"github.com/kami/maven/internal/store"
 )
 
@@ -67,6 +68,44 @@ func parseOrdinal(text string) (int, bool) {
 	return 0, false
 }
 
+// parseReminderCancelChoice is intentionally narrower than parseOrdinal. A
+// task ordinal may appear inside a sentence carrying its transition verb; the
+// reminder list was already offered specifically for cancellation, so the next
+// mutation requires the whole turn to be one affirmative position answer.
+// Questions, negation, two positions and new requests all decline and route as
+// fresh turns instead of cancelling whichever ordinal happened to appear.
+func parseReminderCancelChoice(text string) (int, bool) {
+	if router.IsQuestionShaped(text) {
+		return 0, false
+	}
+	tokens := turnTokens(text)
+	nth, positions := 0, 0
+	for _, tok := range tokens {
+		if reminderCancelNegation(tok) {
+			return 0, false
+		}
+		if n, ok := candidateDigits[tok]; ok {
+			nth, positions = n, positions+1
+			continue
+		}
+		if n, ok := lexicon.Ordinal(tok); ok {
+			nth, positions = n, positions+1
+			continue
+		}
+		if lexicon.IsFillerParticle(tok) || reminderCancelVerbs[tok] ||
+			isReminderCancelTarget(tok) || reminderCancelFrame[tok] {
+			continue
+		}
+		switch tok {
+		case "номер", "вариант", "number", "option", "one":
+			continue
+		default:
+			return 0, false
+		}
+	}
+	return nth, positions == 1
+}
+
 // candidateVerbs — what he wants done with the one he picked. Nothing here is
 // destructive: a task moves forward or is dropped, and both are recorded with a
 // provenance the /tasks page shows.
@@ -112,7 +151,21 @@ func (h *reactiveHandler) resolveCandidate(ctx context.Context, text string, src
 	if sess == nil || len(sess.Candidates) == 0 {
 		return "", false
 	}
+	reminderList := true
+	for _, candidate := range sess.Candidates {
+		if candidate.Kind != "reminder-cancel" {
+			reminderList = false
+			break
+		}
+	}
+	if reminderList && classifyConfirm(text) == confirmNo {
+		h.dialogueSessions.SetCandidates(dialogueIDOf(ctx), h.now(), nil)
+		return "хорошо, ничего не отменяю.", true
+	}
 	nth, ok := parseOrdinal(text)
+	if reminderList {
+		nth, ok = parseReminderCancelChoice(text)
+	}
 	if !ok {
 		return "", false
 	}
@@ -125,6 +178,12 @@ func (h *reactiveHandler) resolveCandidate(ctx context.Context, text string, src
 		return fmt.Sprintf("я назвала только %d.", len(sess.Candidates)), true
 	}
 	pick := sess.Candidates[nth-1]
+	if pick.Kind == "reminder-cancel" {
+		// Unlike a task list, this list was offered in answer to the explicit
+		// question "which reminder should I cancel?" A bare ordinal is the
+		// answer to that question and therefore completes the cancellation.
+		return h.cancelReminderChoice(ctx, pick.Ref, pick.Label), true
+	}
 	status, say, hasVerb := parseCandidateVerb(text)
 	if !hasVerb || pick.Kind != "task" {
 		// Read it back and keep the list: naming one is often the first half of