Add seven stage 0 frames and tighten three more (V-720)

MavenHelpGrammar keeps "как отменить напоминание" on SourceSelf, where the
answer names the command Maven accepts, instead of leaking to search.
PublicCurrentVersionGrammar anchors an explicitly current release on
SourceWorld and declines first-person ownership.

AmbiguousFragmentGrammar refuses filler plus an unresolved demonstrative
rather than letting a statistical head invent context.
ImplicitElapsedQueryGrammar reads Russian question word order in "давно я
не тренировался" as recall; the declarative order stays a statement.
ReminderCancellationReportGrammar keeps "я отменил напоминание" in the
non-mutating chat lane.

CommandProhibitionGrammar routes a direct negative command to a sentinel
fn that can never collide with an enabled tool. ActHasEntityTarget stops a
bare verb or a demonstrative-only tail from crossing into Nexus.

Praxis attention now accepts "что там с X" for the four service names only.
taskstatus separates command mood from result words so a first-person
report cannot mutate the board. question.go exports the open-question and
locative shapes the recall gate reads.

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

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

internal/router/stagezero.go

@@ -22,24 +22,45 @@ package router
 // the fixture can also run them one at a time and see which of them contend for
 // the same utterance, which the cascade hides by stopping at the first match.
 func StageZeroGrammars(acts ActMatcher) []Grammar {
-	grammars := DefaultGrammars(acts)
+	// Negative authority gets first refusal. This structural grammar reads the
+	// command frame, not a substring, and emits a non-executable sentinel. It
+	// must precede the wake-word allowlist fast path: an unusually permissive
+	// matcher may recognise the verb inside "Maven, don't restart nginx", but
+	// an allowlist match cannot turn an explicit prohibition into permission.
+	grammars := []Grammar{CommandProhibitionGrammar()}
+	grammars = append(grammars, DefaultGrammars(acts)...)
+	// A refusal, not a guessed intent. It is safe ahead of every positive rule
+	// because it accepts only filler plus unresolved-reference words.
+	grammars = append(grammars, AmbiguousFragmentGrammar())
 	grammars = append(grammars, SystemTimeDateGrammars()...)
 	// After the time/date rules on purpose: "какой сегодня день" is a clock
 	// question and must keep reaching replySystem, while "что у меня сегодня"
 	// is an agenda question and must not.
 	grammars = append(grammars, AgendaQueryGrammars()...)
+	// Russian can ask "how long since" through word order rather than a
+	// question word. This must land in recall before a statistical head reads
+	// the same past-tense verb as a fact.
+	grammars = append(grammars, ImplicitElapsedQueryGrammar())
 	// Same reason as the agenda rules, for the feeds: "что нового в лентах?"
 	// routed system and answered "пока не умею" (Vikunja #474).
 	// After the agenda rules, which are the narrower claim, and BEFORE the feed
 	// and list rules, which are not: "что такое лента" is a definition question
 	// and the feed rule would take it on the noun alone (V-655).
 	grammars = append(grammars, WorldQueryGrammars()...)
+	// Questions about operating Maven herself are local product help. They sit
+	// beside the world anchors because both decide which side of the personal
+	// boundary owns an answer, in opposite directions.
+	grammars = append(grammars, MavenHelpGrammar())
 	grammars = append(grammars, FeedQueryGrammar())
 	// The list side of the same exposure: a phrasing with no possessive in it
 	// ("список дел") routed system and never reached queryTasks (Vikunja #467).
 	grammars = append(grammars, TaskListGrammar())
 	grammars = append(grammars, ListGrammars()...)
 	grammars = append(grammars, ReminderGrammar())
+	// A first-person report about a cancellation is neither another mutation
+	// nor a memory query. The imperative cancellation pre-route has already had
+	// first refusal before the router runs.
+	grammars = append(grammars, ReminderCancellationReportGrammar())
 	// Before the capture marker, because "отметь" is a capture verb and "отметь
 	// второй пункт" is not a note. The Praxis rules are the narrower claim — a
 	// lifecycle verb AND an item named — so they get first refusal (Vikunja #516).