Read spending from zenmoney in the poller, answer it from facts (#125)

The trust boundary is zenmoney, not maven — they already hold his bank
sessions. So the poller reads /v8/diff/ and writes totals as
facts(kind=env, source=poll:zenmoney); core reads those back when he asks
and never sees the token.

internal/zenmoney sums transactions per currency over a window, skipping
tombstoned rows and transfers between his own accounts, and refuses to
encode a summary built from zero transactions. That refusal is the whole
design: a failed or empty read writes nothing and leaves the last good
total alone, because a zero recited as fact is worse than silence. No
currency conversion either — a figure he can check against his bank beats
one he cannot.

Off unless configured, and the token is read from a FILE rather than a
flag so it never lands in `ps`, in docker-compose.yml, or in shell
history. Nothing about the money is search input, no tick rule reads the
keys, and the log lines name keys, never figures.

The live-credential half is BLOCKED: there is no zenmoney account or token
here, so everything is verified against a recorded diff fixture.

cmd/mavend/actions_query.go

@@ -62,6 +62,11 @@ var querySources = []querySource{
 	// matcher requires a task noun or an explicit "что … сделать", so a
 	// date-bearing question still reaches the calendar.
 	{"tasks", (*reactiveHandler).queryTasks},
+	// Before the recall sources too: "сколько я потратил?" is a question about
+	// the money facts the poller wrote, and the notes pass would otherwise
+	// answer it from whatever he once said about spending. Its matcher needs a
+	// money noun plus an actual ask, so "я потратил весь день" is untouched.
+	{"money", (*reactiveHandler).queryMoney},
 	{"calendar", (*reactiveHandler).queryCalendar},
 	{"weather", (*reactiveHandler).queryWeather},
 	{"embed", (*reactiveHandler).queryEmbed},